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AN

INTRODUCTION

TO

PHYSIOLOGICAL anv SYSTEMATICAL

BOTANY.

BY

Sir JAMES EDWARD SMITH, M.D. F.R.S.
&c. &c.

PRESIDENT OF THE LINNJEAN SOCIETY.
“ CONSIDER THE LILIES OF THE FIELD, HOW THEY GROW.”

FOURTH EDITION.

London:

PRINTED FOR LONGMAN, HURST, REES, ORME, AND BROWN,
PATERNOSTER-ROW.

1819.

Printed ly R, and A. Taylor, Shoe-lane.

TO

THE HONOURABLE AND RIGHT REVEREND

SHUTE,
LORD BISHOP OF DURHAM,

My Lorp,

Tze circumstances which induce me to
solicit your Lordship’s protection for the fol--
lowing pages are such, that [ trust they will
ensure pardon for myself, and more indulgence
for my performance than I might expect, even
from your Lordship’s usual goodness towards

me.

The contents of these pages were, in a very
unfinished state, honoured with the approbation
and encouragement of an excellent and lamented
lady, to whom they were destined to be offered
an their present less unworthy condition. Lf
should have been proud to have sheltered them
under her patronage, because I have always

found the most intellhgent critics the most in-

a2

1V DEDICATION.

~

dulgent. Their general tendency at least, as
calculated to render an interesting and useful
science accessible, and in every point eligible,
to the more accomplished and refined of her own
sex, could not fail to have been approved by
her, who knew and exemplified so well the value
and importance of such pursuits, and their in-
estimable effects upon the mind. These hopes,
which my late honoured friend and patroness
had, with her usual benignity, encouraged, are
now most unhappily defeated, andI have no re-
source but in your Lordship, who is no stranger
to my pretensions, nor to my sentiments, and in
whom I have not now for the first time to seek

an able and enlightened patron.
I remain, with the profoundest respect,
my Lord,
your Lordship’s most obliged

and obedient servant,

J. E. SMITH.

Norwich,
Noy, 15, 1807.

EFACE, OS

a

4.
ee OE

Arrer the many elementary works on Botany
which have appeared in various languages, any
new attempt of the same kind may, at first sight,
seem unnecessary. But when we consider the ra-
pid progress of the science within a few years, in
the acquisition and determination of new plants,
and especially the discoveries and improvements
in vegetable physiology : when we reflect on the
views with which those fundamental works of
Linneus, the basis of all following ones, were
_ composed, and to whom they were addressed,
we must be aware of their unfitness for purposes
of general and popular utility, and that some-
thing else is wanting. If we examine the mass
of introductory books on botany in this light, we
shall find them in some cases too elaborate and
intricate, in others too obscure and imperfect ;
they are also deficient in that very pleasing and
instructive part of botany the anatomy and phy-
_siology of plants. There are indeed works, such
as Rose’s Elements of Botany, and Darwin’s Phy-
tologia, with which no such faults can be found.

/

v1 PREFACE.

The former is a compendium of Linnean learn-
ing, the latter a store of ingenious philosophy ;
bat they were designed for philosophers, and are
not calculated for every reader. Linnzus and his
scholars have generally written in Latin. They
addressed themselves to physicians, to anato-
mists, to philosophers, little thinking that their
science would ever be the amusing pursuit of the
-young, the elegant and the refined, or they
~would have treated the subject differently. It ap-
pears to me, therefore, that an introductory pub-
lication is still desirable in this country, on an
original plan, easy, comprehensive, and fit for
general use; and such were the reasons which
first prompted me to the undertaking.

When, however, I had proceeded a consider-
‘able way in its execution, I found that sucha
work might not only serve to teach the first out-
lines of the science, but that it might prove a
vehicle for many observations, criticisms, and
communications, scarcely to be brought together
on any other plan; nor did it appear any ob-
jection to the general use of the book, that, be-
sides its primary intention, it might be capable
of leading into the depths of botanical philoso-
phy, whether physiological, systematical, or cri-

PREFACE. Vil

tical, any student who should be desirous of pro-
ceeding so far. A volume of this size can indeed
be but elementary on subjects so extensive; but
if it be clear and intelligible as far as it goes,
serving to indicate the scope of the science of
botany, and how any of its branches may be
cultivated further, my purpose is answered. The
subject has naturally led me to a particular cri-
ticism of the Linnzan system of arrangement,
which the public, it seems, has expected from
me. Without wasting any words on those specu-
lative and fanciful changes, which the most ig-
norant may easily make, in an artificial system;
and without entering into controversy, with the
very few competent. writers who have proposed
any alterations; I have simply stated the result
of my own practical observations, wishing by
the light of experience to correct and to confirm
what has been found useful, rather than rashly
to overthrow what perhaps cannot on the whole
be improved.

As the discriminating characters of the Lin-
nean system are founded in nature and fact,
and depend upon parts essential to every species
of plant when in perfection; and as the applica-
tion of them to practice is, above all other sy-

Vill PREFACE.

stems, easy and intelligible; I conceive nothing
more useful can be done than to perfect, upon
its own principles, any parts of this system that
experience may show to have been originally -
defective. This is all I presume to do. Specu-°
lative alterations in an artificial system are end-
less, and scarcely answerany more useful purpose
than changing the order of letters in an alphabet.
The philosophy of botanical arrangement, or the
study of the natural affinities of plants, is quite
another matter. But it would be as idle, while
we pursue this last-mentioned subject, so deep
and so intricate that its most able cultivators are
only learners, to lay aside the continual use of
the Linnzan system, as it would be for philolo-
gists and logicians to slight the convenience, and
indeed necessity, of the alphabet, and to substi-
tute the Chinese character in its stead. If the
following pages be found to elucidate and to con-
firm this comparison, I wish the student to keep
it ever 1n view.

The illustration of the Linnean system of
classification, though essential to my purpose,
is however but a small part of my aim. © To
explain and apply to practice those beautiful
principles of miethod, arrangement and dis-

PREFACE. 1X

crimination, which render botany not merely
an amusement, a motive for taking air and ex-
ercise, or an assistance to many other arts and
sciences; but a school for the mental powers,
an alluring incitement for the young mind to
try its growing strength, and a confirmation of
the most enlightened understanding in some
of its sublimest most important truths. That
every path tending to ends so desirable may be
accessible, I have not confined myself to sy-
stematical subjects, wide and various as they
are, but I have introduced the anatomy and
physiology of plants to the botanical student,
wishing to combine all these several objects ;
so far at least that those who do not cultivate
them all, may be sensible of the value of each
in itself, and that no disgraceful rivalship or
contempt, the offspring of ignorance, may be
felt by the pursuers of any to the prejudice of
the rest. art!

I have treated of physiological and anato-
mical subjects in the first place, because a
true knowledge of the structure and parts of
plants seems necessary to the mght under-
standing of botanical arrangement; and [I
trust the most superficial reader will here find

e

X PREFACE.

enough for that purpose, even though he should
not be led to pursue these subjects further
by himself. I have every where aimed at fa-
miliar illustrations and examples, referring, as
much as possible, to plants of easy acquisition.
In the explanation of botanical terms and cha-
racters, I have, besides furnishing a new set of
plates with references to the body of the work,
always cited a plant for my purpose by its scien-
tific name, with a reference to some good and
sufficient figure. For this end I have generally
used either my own works English and Exotic
Botany, all the plates of which, as well as of
the present volume, are the performance of the
same excellent botanist as well as artist; or
Curtis's Magazine, some of which also was
drawn by Mr. Sowerby, but the greater part
by the no less ingenious Mr. Edwards. I have
chosen these as the most comprehensive and
popular books, quoting others only when these
failed me, or when I had some particular end
in view. If this treatise should be adopted for
general use in schools or families, the teacher
at least will probably be furnished with those
works, and will accommodate their contents
to the use of the pupils. Iam aware of the

PREFACE. Xi

want of a systematical English description of
British plants, on the principles of this Intro-
duction ; but that deficiency I hope as soon as
possible to supply. In the mean while Dr.
Withering’s work. may serve the desired pur-
pose, attention being paid only to his original
descriptions, or to those quoted from English
writers. His index will atone for the changes
I cannot approve in his system. Wherever
my book may be found deficient in the ex-
planation of his or any other terms, as I pro-
fess to retain only what are necessary, or in
some shape useful, the Language of Botany,
by Professor Martyn, will prove extremely ser-
viceable.

Having thus explained the use and intention
of the present work, perhaps a few remarks on
the recommendations of the study of Botany,
besides what have already been suggested, may
not here be misplaced.

I shall not labour to prove bai delightful and
instructive it is to

‘‘ Look through nature up to Nature’s God.”
g p

Neither, surely, need I demonstrate, that if
any judicious or improved use is to be made of

Xll PREFACE.

the natural bodies around us, it must be expect-
ed from those who discriminate their kinds and
study their properties. Of the benefits of natu-
ral science in the improvement of many arts,
no one doubts. Our food, our physic, our lux-
uries are improved by it. By the inquiries of
the curious, new acquisitions are made in re-
mote countries, and our resources of various
kinds are augmented. The skill of Linneus by
the most simple observation, founded however
on scientific principles, taught his countrymen

to destroy an insect, the Cantharis navalis,
which had-cost the Swedish government many
thousand pounds a year by its ravages on the
timber of one dockyard only. After its meta-
morphoses, and the season when the fly laid its
eggs, were known, all its ravages were stopped
by immersing the timber in water during that
period. The same great observer, by his bo-
tanical knowledge, detected the cause of a
dreadful disease among the horned cattle of the
north of Lapland, which had previously been
thought equally unaccountable and irremedi-
able, and of which he has given an exquisite
account in his Lapland tour, as well as under
Cicuta virosa, Engl. Bot. t. 479, in his Flora

PREFACE. X1ll

Lapponica. One man in our days, by his sci-
entific skill alone, has given the bread-fruit to
the West-Indies, and his country justly honours
his character and pursuits. All this is acknow-
ledged. We are no longer in the infancy of
science, in which its utility, not having been
proved, might be doubted, nor is it for this that
Icontend. I would recommend botany for its
own sake. I have often alluded to its benefits
as a mental exercise, nor can any study exceed
it in raising curiosity, gratifying a taste for
beauty and ingenuity of contrivance, or sharpen-
ing the powers of discrimination. What then
can be better adapted for young persons? The
chief use of a great part of our education is no
other than what I have just mentioned. The
languages and the mathematics, however valu-
able in themselves when acquired, are even more
so as they train the youthful mind_ to thought
and observation. In Sweden Natural History
is the study of the schools, by which men rise
to preferment; and there are no people with
more acute or better regulated minds than the
Swedes. :

To those whose minds and understandings
are already formed, this study may be recom-

X1V PREFACE.

mended, independently of all other considera-—
tions, as a rich source of innocent pleasure.
Some people are ever inquiring “ what is the use”
of any particular plant, by which they mean
‘‘ what food or physic, or what materials for
the painter or dyer does it afford?” They look
on a beautiful flowery meadow with admiration,
only in proportion as it affords nauseous drugs
or salves. Others consider a botanist with re-
spect only as he may be able to teach them some
profitable improvement in tanning, or dyeing,
by which they may quickly grow rich, and be
then perhaps no longer of any use to mankind
or to themselves. They would permit their
children to study botany, only because it might
possibly lead to professorships, or other lucra-
tive preferment.

These views are not blameable, but they are
not the sole end of human existence. Is it not
desirable to call the soul from the feverish agi-
tation of worldly pursuits, to the contemplation
of Divine Wisdom in the beautiful economy of
Nature? Is it not a privilege to walk with God
in the garden of creation, and hold converse
with his providence? If such elevated feelings
do not lead to the study of Nature, it cannot

PREFACE. XV

far be pursued without rewarding the student
by exciting them.

Rousseau, a great judge of the human heart
and observer of human manners, has remarked,
that “when science is transplanted from the
mountains and woods into cities and worldly so-
ciety, it loses its genuine charms, and becomes
a source of envy, jealousy and rivalship.” This
is still more true if it be cultivated as a mere
source of emolument. But the man who loves
botany for its own sake knows no such feelings,
nor is he dependent for happiness on situations
or scenes that favour their growth. He would
find himself neither solitary nor desolate, had
he no other companion than a “ mountain
daisy,” that “ modest crimson-tipped flower,”
so sweetly sung by one of Nature’s own poets.
The humblest weed or moss will ever afford
him something to examine or to illustrate, and
a great deal to admire. Introduce him to the
magnificence of a tropical forest, the enamelled
meadows of the Alps, or the wonders of New
Holland, and his thoughts will not dwell much
upon riches or literary honours, things that _

* Play round the head, but come not near the heart.”

One idea is indeed worthy to mix in the pure

XV1 PREFACE.

contemplation of Nature, the anticipation of the
pleasure _ we may have. to. bestow on. kindred
minds \ with. our own, in sharing with them our
discoveries and our acquisitions. This is truly
an ‘object worthy of. a good man, the pleasure
of communicating virtuous disinterested. plea-
sure to those who have the same tastes with our-
selves; or of guiding young ingenuous minds
to worthy pursuits, and facilitating their acqui-
sition of what we have already obtained. If
honours and respectful consideration reward
such motives, they flow from a,pure source.
The giver and the receiver are alike_invulne-
rable, as.well as inaccessible, to ‘envy, jealousy
or rivalship,” and may pardon their attacks
without an effort. : , hac 7

The natural history of. animals, in many
respects even more interesting than botany to
man as an animated being, and, more striking
in some of the phxnomena which it displays,
is in other points less pleasing to a tender and
delicate mind. In botany all is elegance and
delight. No painful, disgusting, unhealthy ex-
periments or inquiries are to be made. ., Its
pleasures spring up under our feet, and, as we
pursue them, reward us with health and serene

PREFACE. XVil

satisfaction. None but the most foolish or de-
praved could derive any thing from it but what
is beautiful, or pollute its lovely scenery with
unamiable or unhallowed images. Those who
do so, either from corrupt taste or malicious
design, can be compared only to the fiend en-
tering into the garden of Eden.

Let us turn from this odious picture to the
contemplation of Nature, ever new, ever abun-
dant in inexhaustible variety. Whether we

scrutinize the damp recesses of woods in the.

wintry months, when the numerous tribes of
mosses are displaying their minute but highly
interesting structure ; whether we walk forth in
the early spring, when the ruby tips of the haw-
thorn-bush give the first sign of its approaching
vegetation, or a little after, when the violet
welcomes us with its scent, and the primrose
with its beauty; whether we contemplate in
succession all the profuse flowery treasures of
the summer, or the more hidden secrets of Na-
ture at the season when fruits and seeds are
forming; the most familiar objects, like old
friends, will always afford us something to study
and to admire in their characters, while new

discoveries will awaken a train of new ideas. The. -

b

XVH1 PREFACE.

yellow blossoms of the morning, that fold up their
delicate leaves as the day advances ; others
that court and sustain the full blaze of noon;
arid the, pale night-scented tribe, which ex-
pand, and diffuse their very sweet fragrance,
towards evening, will all please in their turn.
Though spring is the season of hope and novel-
ty, to a naturalist more especially, yet the wise
provisions and abundant resources of Nature,
in the close of the year, will yield an observing
mind no less pleasure, than the rich variety
of her autumnal tints affords to the admirers
of her external charms. The more we study
the works of the Creator, the. more wisdom,
beauty and harmony become manifest, even
to our limited apprehensions ; and while we
admire, it is impossible not to adore.

< Soft roll your incense, herbs, and fruits, and flowers,
In mingled clouds, to Him, whose sun exalts,
Whose breath perfumes you, and whose pencil paints!”

CONTENTS.

CHAPTER I.

Distrncrions ‘between animals, vegetables and fossils.
On the vital principle essential to the two former.... p- 1
~ CHAPTER II.

Definition of natural history, and Mcicahady botany. Of

>

eo eee ea ques chlo wewdssdeigsip> O

CHAPTER III.

Of the cuticle or epidermis ......eeesesenseeceees Ds 13

CHAPTER LV.

Of the cellular integument 2... cee eeeeereeeeeees Pld

. CHAPTER V.
Of the bark ash bina x sudhn mek oa gee es ee eee ee

CHAPTER VI.

Of the wood @eeeetoee ee en PRP er ee rae wet eS

CHAPTER VL.
Of Se ae i lak ea tk an 30

CHAPTER VIII.

Of the sap-vessels, and course of the sap; with Mr. Knight’s

theory of vegetation eee eer Pee ree

CHAPTER IX.

Of the sap, and insensible perspiration ......ee00-. p- 48

b2

A/00"|

xx CONTENTS.

CHAPTER X.
Of the secreted fluids of plants. Grafting, Heat of the vege-
UTE WY Ne s'n eeu tin vdumee ones op tes dlemuneeee

CHAPTER XI.
The process of vegetation, Use of the cotyledons ...p.72

CHAPTER XII.
Of the root and its different kinds ecoeee ° eoecececoe p- 79

CHAPTER XIII.
Different kinds of stems and stalks of plants ........ p. 90
: CHAPTER XIV.
Of Dalle cas ab nebo @eeeee? eoccccecerececscvevel: 104
CHAPTER XV. |
Of leaves, their situations, insertions, surfaces, and various

forms pete ere aeeebancsseenfQMul leer cl rae es 110

CHAPTER XVI.

OF thé Tahctions Of lédves’ ¢ ... cic v.c00:0 0 « vine e's oe isin fis ee

CHAPTER XVII.
Of the several kinds of fulcra, or appendages to a plant. p. 166

CHAPTER XVIII.
Of the inflorescence, or mode of flowering, and its various
forms £88 08 ms emis badd Hdl Medio eee ean ag eee
CHAPTER XIX.
Of the flower and frit. ii, SKA SSDs edi ike enone PATS

| CHAPTER XX. ;
Of the peculiar functions of the stamens and pistils, with the
experiments and observations of Linnzus and others on
that subject EEE TT eee NT he

CONTENTS. xix”

CHAPTER XXI.

Of the diseases of plants, particularly as illustrative of their
vital principle FEDS SS aes See Se eee eS 68 e's p. 259

CHAPTER XXII. .

Of the systematical arrangement of.plants. Natural and
artificial methods. Genera, species and varieties. No-
MTAIOES 6 adn ins maghs spades dees coebanee p. 267

CHAPTER XXIII.
Explanation of the Linnean artificial system ...... p. 296
CHAPTER XXIV.
Illustrations of the Linnean classes and orders ...6. p.311

Explanation of the plates ....ecceceveseceee Ps O99

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INTRODUCTION

TO

PHYSIOLOGICAL anno SYSTEMATICAL

BOTANY.

CTA Pew’?

.

DISTINCTIONS BETWEEN ANIMALS, VEGETABLES,
AND FOSSILS.—ON THE VITAL PRINCIPLE ES-
SENTIAL TO THE TWO FORMER.

"Tuose who with a philosophical eye have confem-
plated the productions of Nature, have all, by common
consent, divided them into three great classes, called
the Animal, the Vegetable, and the Mineral or Fossil
Kingdoms. These terms are still in general use, and
the most superficial observer must be struck with their
propriety. The application of them seems at first
sight perfectly easy, and in general itis so. Difficul
ties occur to those only who look very deeply into the
subject. | |

Animals have an organized structure which regu-
larly unfolds itself, and is nourished and supported by

B

g DISTINCTIONS BETWEEN ANIMALS

air and food ; they consequently possess life, and are
subject to death; they are moreover endowed with
sensation, and with spontaneous, as well as voluntary,
motion. |

Vegetables are organized, supported by air and
food, endowed with life and subject to death as well
as animals. They have in some instances spontaneous,
though we know not that they have voluntary, motion.
They are sensible to the action of nourishment, air,
and light, and either thrive or languish according to
the wholesome or hurtful application of these stimu-
lants. ‘This is evident to all who have ever seen a
plant growing in a climate, soil, or situation, not suit-,
able to it. Those who have ever gathered a rose,
know but too well how soon it withers; and the fa-
miliar application of its fate to that of human life and
beauty is not more striking to the imagination than
philosophically and literally true. The sensitive plant
is a more astonishing example of the capability of
vegetables to be acted upon as living bodies. Other
instances of the same kind we shall hereafter have
occasion to mention.

The spontaneous movements of plants are almost as
readily to be observed as their living principle. The |
general direction of their branches, and especially of
the upper surface of their leaves, though repeatedly
disturbed, to the light; the unfolding and closing of
their flowers at stated times, or according to favourable
or unfavourable circumstances, with some still more

AND VEGETABLES. 3

curious particulars to be explained in the sequel of
this work, are actions undoubtedly depending on their
vital principle, and are performed with the greater
facility in proportion as that principle is in its greatest ,
vigour. Hence arises a question whether Vegetables
are endowed with sensation. As they possess life,
irritability and motion, spontaneously directing their
organs to what is natural and beneficial to them, and
flourishing according to their success in satisfying their
wants, may not the exercise of their vital functions be
attended with some degree of sensation, however low,
and some consequent share of happiness? Such a
supposition accords with all the best ideas we can form
of the Divine Creator; nor could the consequent un-
easiness which plants must suffer, no doubt in a very
low degree likewise, from the depredations of animals,
bear any comparison with their enjoyment on the
whole. However this may be, the want of sensation is.
most certainly not to be proved with regard to Vege-
tables, and therefore of no use as a practical means of
distinguishing them, in doubtful cases, from Animals.
Some philosophers* have made a locomotive power
peculiarly characteristic of Animals, not being aware
of the true nature of those half-animated beings called
Corals and Corallines, which are fixed, as immoyeably
as any plants, to the bottom of the sea, while indeed
many living vegetables swim around them, unattached

* Jungius, Boerhaave, Ludwig and many others.

B2

4 DISTINCTIONS BETWEEN ANIMALS, ETC.

to the soil, and nourished by the water in which they

float. Some™* have characterized Animals as nou-

rished by their internal, and Vegetables by their exter-
mal surface, the latter having no such thing as an inter-
mal stomach. This is ingenious and tolerably correct ;
‘but the proofs of it must fail with respect to those
minute and simply-constructed ‘animals the Polypes,

and the lower tribes of Worms, whose feelers, put
forth into the water, seem scarcely different from roots —
-seeking their food in the earth, and some of which
amay be turned inside out, like a glove, without any
disturbance of their ordinary functions. The most
‘satisfactory remark I have for a long time met with on
this difficult subject is that of M. Mirbel, in his Zrazté
d Anatomie et de Physiologie Véyétalest, a work I

shall often have occasion to quote. He observes,

wol. i. p. 19, “ that plants alone have a power of de-

riving nourishment, though not indeed exclusively,

from inorganic matter, mere earths, salts or airs, sub-

stances certainly incapable of serving as food for any

animals, the latter only feeding on what is or has been

organized matter, either of a vegetable or animal

nature. So'that it should seem to be the office of

vegetable life alone to transform dead matter into or-

ganized living bodies.” This idea appears to me so_

just, that I have in vain sought for any exception to it.

Let us however descend from these philosophical

* Dr. Alston, formerly professor of botany at Edinburgh.
+ Published at Paris a few years since, in two vols. 8vo.

&

MINERAL KINGDOM. a

speculations to purposes of practical utility. It is suf-
ficient for the young student of Natural History to
know, that in every case in which he can be in doubt
whether he has found a plant or one of the lower
_ orders of animals, the sitaple experiment of burning
will decide the question. The smell of a burnt bone,
coralline, or other animal substance, is so peculiar that
it can never be mistaken, nor does any known vege-
table give out the same odour.

The Mineral Kingdom can never be confounded

with the other two. Fossils are masses of mere dead
unorganized matter, subject to the laws of chemistry
alone; growing indeed, or increasing by the mecha-
nical addition of extraneous substances, or by the laws
of chemical attraction, but not fed by nourishment
taken into an organized structure. ‘Their curious
crystallization bears some resemblance to organization,
but performs none of its functions, nor is any thing
like a vital principle to be found. in this department
of Nature.
If itbe asked what is this vital principle, so essential
to animals and vegetables, but of which fossils are
destitute, we must own our complete ignorance. We
know it, as we know its Omnipotent Author, by its
effects.

Perhaps in the fossil kingdom heat may be equi-
valent to a vital principle; but heat is. not the vital
principle of organized bodies, though probably a con-
sequence of that principle.

6 ON THE VITAL PRINCIPLE.

Living bodies of animals and plants produce heat ;
and this phenomenon has not, I think, been entirely
explained on any chemical principles, though in fossils
the production of heat is in most cases tolerably well
accounted for. In animals it seems to have the closest
possible connexion with the vital energy. But the
effects of this vital energy are still more stupendous in
the operations constantly going on in every organized
body, from our own elaborate frame to the humblest
moss or fungus. Those different fluids, so fine and
transparent, separated from each other by membranes
as fine, which compose the eye, all retain their proper
situations (though each fluid individually is perpetually
removed and renewed) for sixty, eighty, or a hundred
years, or more, while /ife remains. So do the infinitely
small vessels of an almost invisible insect, the fine and
pellucid tubes of a plant, all hold their destined fluids,
‘conveying or changing them according to fixed laws,
but never permitting them to run into confusion, so
long as the vital principle animates their various forms.
But no sooner does death happen, than, without any
alteration of structure, any apparent change in their
material configuration, all is reversed. ‘The eye loses
its form and brightness ; its membranes let go their
contents, which mix in confusion, and thenceforth
yield to the laws of chemistry alone. Just so it hap-
pens, sooner or later, to the other parts of the animal
as well as vegetable frame. Chemical changes, putre-
faction and destruction, immediately follow the total

ON THE VITAL PRINCIPLE. 7

privation of life, the importance of which becomes
instantly evident when it is no more. I humbly con-
ceive therefore, that if the human understanding can
in any case flatter itself with obtaining, in the natural
world, a glimpse of the zmmediate agency of the Deity,
itis in the contemplation of this vital principle, which
seeins independent of material organization, and an
impulse of his own divine energy.

Cae See Li.

—<ia

DEFINITION OF NATURAL HISTORY, AND PAR-
TICULARLY BOTANY.—OF THE GENERAL TEX-
TURE. OF PLANTS.

Narvrat History properly signifies that study by
which we learn to distinguish from one another the
natural bodies, whether Animal, Vegetable, or Mineral,
around us; to discover as much as possible their nature
and properties, and especially their natural dependence
on each other in the general scale of beings. In a more
extensive sense it may be said to teach their secondary
properties, or the various uses to which they have been,
or may be, converted, in the service of mankind or of
other animals ; inasmuch as an acquaintance with their
natural qualities is our only sure guide to a knowledge
of their artificial uses. But as this definition would
include many arts and sciences, each of them sufficient
to occupy any common mind, as Agriculture, Diete-
tics, Medicine, and many others, it is sufficient for a
philosophical naturalist to be acquainted with the ge-
neral principles upon which such arts and sciences are
founded.
- That part of Natural History which concerns plants
is called Botany, from Boteéyy, the Greek word for a
herb or grass. It may be divided into three branches :

DEFINITION OF BOTANY. G9

Ist, The physiology of plants, or a knowledge of the
structure and functions of their different parts; 2dly,
‘The systematical arrangement and denomination of
their several kinds; and 3dly, Their ceconomical or
inedical properties. All these objects should.be kept
in view by an intelligent botanist. The two first are
of essential service to each other, and the last is only
to be pursued, with any certainty, by such as are versed
in the other two. The present publication is intended
to explain the fundamental principles of them all, with
as much practical illustration as may be necessary for
those who wish to become well acquainted with this
delighttul science. Botany has one advantage over
many other useful and necessary studies, that even its
first beginnings are pleasing and profitable, though
pursued to ever so small an extent; the objects with
which it is conversant are in themselves charming, and
they become doubly so to those who contemplate them
with the additional sense, as it were, which science
gives; the pursuit of these objects is an exercise no
less healthful to the body, than the observation of their
~ laws and characters is to the mind. 7

In studying the functions of the Vegetable fais
we must constantly remember that it is not merely a
collection of tubes or vessels holding different fluids,
but that it is endowed-with life, and consequently able
not only to imbibe particular fluids, but to alter their
nature according to certain laws, that is, to form pecu-
liar secretions. This is the exclusive property of a

10 GENERAL TEXTURE OF PLANTS.

living being. Animals secrete milk and fat from food
which has no resemblance to those substances ; so Ve-
getables secrete gum, sugar, and various resinous sub-
stances from the uniform juices of the earth, or perhaps
from mere water and air. ‘The most different and dis-
cordant fluids, separated only by the finest film or
membrane, are, as we have already observed, kept
perfectly distinct, while life remains; but no sooner
does the vital principle depart, than secretion, as well
as the due preservation of what has been secreted, are
both at an end, and the principle of dissolution reigns
absolute. | Yee

Before we can examine the physiology of vege-
tables, it is necessary to acquire some idea of their
structure.

Much light has been thrown upon the general texture |
of Vegetables by the microscopic figures of Grew,
Malpighi and others, repeated by Dr. Thornton in his
Illustration of the Linnean System, but more espe-
cially by the recent observations and highly magnified
dissections of M. Mirbel. See his Table of Vegetable
Anatomy in the work already mentioned. From pre-
ceding writers we had learned the general tubular or
vascular structure of the vegetable body, and the exist-
ence of some peculiar spirally-coated vessels in many
plants. On these slender foundations physiologists
have, at their pleasure, constructed various theories,
relative to the motion of the sap, respiration and other
functions, presumed to be analogous to those of ani-

GENERAL TEXTURE OF PLANTS. 1]

mals. Theanatomical observations of Mirbel go further
than those of Grew, &c., and it is necessary to give
a short account of his discoveries.

He finds, by the help of the highest magnifying
powers, that the vegetable body is a continued mass of
tubes and cells; the former extended indefinitely, the
latter frequently and regularly interrupted by transverse
partitions. These partitions being ranged alternately
in the corresponding cells, and each cell increasing
somewhat in diameter after its first formation, except
where restrained by the transverse partitions, seems to
account for their hexagonal figure*. See Tab. I. f. a.
The membranous sides of all these cells and tubes are
very thin, more or less transparent, often porous, va-
riously perforated or torn. Of the tubes, some are
without any lateral perforations, f- b, at least for a con-
siderable extent ; others pierced with holes ranged in a
close spiral line, fc; in others several of these holes’
run together, as it were, into interrupted spiral clefts,

f. d; and in some those clefts are continued, so that
the whole tube, more or less, is cut into a spiral line,
fie; which, in some young branches and tender
leaves, will unroll to a great extent, when they are
gently torn asunder. The cellular texture especially is
extended to every part of the vegetable body, even
into the thin skin, called the cuticle, which covers

* In microscopic figures they are generally drawn like circles inter=
secting each other.

12 GENERAL TEXTURE OF PLANTS.

aa

every external part, and into the fine hairs or down
which, in some instances, clothe the cuticle itself.

Before we offer any thing upon the supposed func-
tions of these different organs, we shall take a general
view of the Vegetable body, beginning at the external
part and proceeding inwards. 5

13

CHAPTER IIl.

OF THE CUTICLE OR EPIDERMIS.

Every part of a living plant is covered with a skin
or membrane called the cuticle, which same denomina-
tion has been giver by anatomists to the scarf skin that
covers the animal body, protecting it from the injuries
of the air, and allowing of due absorption and perspi-
ration through its pores.

There is the most striking analogy between the
animal and the vegetable cuticle. . In the former, it
varies in thickness from the exquisitely delicate film
which covers the eye, to the hard skin of the hand or
foot, or the far coarser covering of a Tortoise or Rhi-
noceros; in the latter, it is equally delicate on the parts
of a flower, and scarcely less hard on the leaves of the
Pearly Aloe, or coarse on the trunk of a Plane tree.
In the numerous layers of this membrane continually
peeling off from the birch, we see a resemblance to
the scales which separate from the shell of a Tortoise.
By maceration, boiling, or putrefaction, this part is se-
parable from the plant as well as from the animal,
being, if not absolutely incorruptible, much less prone
to decomposition than the parts it covers. The vital
principle, as far as we can judge, seems to be extinct
in it.

14 OF THE CUTICLE OR EPIDERMIS.

The cuticle admits of the passage of fluids from
within as well as from without, but in a due and defi-
nite proportion in every plant: consequently it must be
porous; and the microscope shows, what reason would
teach us to expect, that its pores are different in dif-
ferent kinds of plants. In very succulent plants, as
Aloes, a leaf of which being cut off will lie for many
weeks in the sun without drying entirely, and yet when .
partly dry will become plump again in a few hours if
plunged into water, the cuticle must be very curiously
constructed, so as to admit of ready absorption, and
very tardy perspiration. Such plants are accordingly
designed toinhabit hot sandy countries, where they are
long exposed to a burning sun, with very rare supplies
of rain.

This part allows also of the passage of air, as is
proved by experiments on the functions of leaves.
Light probably acts through it, as the cuticle is a co-
lourless membrane. We know the effects of light to
be very important in the vegetable ceconomy.

But though this fine membrane admits extraneous
substances, so as to have their due effect upon the
vegetable constitution, according to fixed laws, it no
less powerfully excludes all that would be injurious to
the plant, either in kind or proportion, Against heat
or cold it proves, in general, buta feeble defence ; but
when clothed with hair or wool, it becomes a very
powerful one. Against the undue action of the atmo-
sphere it is so important a guard, that, when any tender

OF THE CUTICLE OR EPIDERMIS. 15

growing part is deprived of it, the greatest mischiefs
ensue. It formsin the Vegetable, as well as the Ani-
mal, a fine but essential barrier between life and de-
struction.

Some have imagined that the cuticle gave form to
the vegetable Lody, because it sometimes being over
tight causes contractions on the stem of a tree, as in
the plum or cherry, and because it is found to be
cracked wherever an unnatural excrescence is produced
on the bark. No doubt the cuticle is formed so as to
accommodate itself only to the natural growth of the
plant, not to any monstrosities, and those lumps cause
it to burst; just as it happens to ripe fruits in very wet
seasons. ‘Their cuticle is constructed suitably to their
usual size_or plumpness, but not to any immoderate
increase from too great absorption of wet. If the cuti-
cle be removed from any part, no swelling follows, as it
would if this membrane only kept the tree in shape.

The extension of the cuticle is astonishing, if we
consider that it is formed, as Grew well observes, on
the tenderest embryo, and only extended during the
growth of the plant, and that it appears not to have
any connexion with the vascular or living part of the ©
vegetable body. But though so accommodating in
those parts where it is wanted, on the old trunks of
most trees it cracks in every direction, and in many is
entirely obliterated, the old dead layers of their bark
performing all the requisite offices of a cuticle.

M. Mirbel indeed, though he admits the importance

16 OF THE CUTICLE OR EPIDERMIS.

of this part in the several ways above mentioned, con-
tends that it is not a distinct organ like the cuticle of
animals, but merely formed of the cellular parts of the
plant dilated and multiplied, and changed by their new
situation. ‘This is very true; but upon the same prin- |
ciple the human cuticle can scarcely be called a distinct
organ. Its texture is continually scaling off externally,
and it is supplied with new layers from within. Just
so does the cuticle of the Birch peel off in scales, se-
parable, almost without end, into smaller ones.

Examples of different kinds of cuticle may be seen
in the following plants.

On the Currant tree it is smooth, and scales off in
large entire flakes, both from the young branches and
old stem. The same may be observed in the Elder.

The fruit of the Peach and the leaf of the Mullein
have a cuticle covered with dense and rather harsh
wool, such as is found on many Mexican plants, and
on more Cretan ones. The latter we know grow in
open places under a burning sun.

The leaf of the White Willow is clothed with a fine
silky or satiny cuticle.

The cuticle of the Betony, and of many other
plants, is extended into rigid hairs or bristles, which
in the Nettle are perforated and contain a venomous
fluid.

On the fruit of the Plum, and on many leaves, we
find a blueish dry powder covering the cuticle, which
is a resinous exudation, and it is difficult to wet the

OF THE CUTICLE OR EPIDERMIS. 17

surface of these plants. Rain trickles over them in
large drops. -

In the Cork tree, the Common Maple, and even
the Dutch Elm, the cuticle is covered with a fungous
substance most extraordinary in its nature, though
familiar to us as cork.

In grasses and some other plants the ingenious Sir
H. Davy has found a flinty substance in the cuticle.

What seems to be the cuticle on the trunk of the
Plane, the Fir, and a kind of Willow called Salix
triandra, vather consists of scales of bark, which
having performed their functions and become dead
matter, are rejected by the increasing bark beneath
them; and this accords with M. Mirbel’s idea of the
cuticle. The old layers of bark in the Chesnut, Oak,
and many other trees, though not cast off, are of the
same nature; and these under the microscope exhibit
the same cellular texture as the real cuticle.

18

CHAPTER IV.

ei

OF THE CELLULAR INTEGUMENT.

Iuaepiatery under the Cuticle we find a succulent
cellular substance, for the most part of a green colour,
at least in the leaves and branches, which is called by
Du Hamel the Enveloppe cellulaire, and by Mirbel
the Zissu herbacé. ‘This is in general the seat of
colour, and in that respect analogous to the re¢e
mucosum, or pulpy substance situated under the hu-
man cuticle, which is pale in the European, and black
in the Negro; but we must carry the analogy no
further, for these two parts perform no functions in
-common. Du Hamel supposed this pulp to form the
cuticle; but this is improbable, as his experiments
show, when that membrane is removed, that the
Cellular Integument exfoliates, at least in trees, or is
thrown off in consequence of the injury it has sus-
tained, and a new cuticle, covering a new layer of the
same succulent matter, is formed under the old one.
Annual stems or branches have not the same power,
any more than leaves. ,
But little attention has been paid to this organ till
lately, though it is very universal, even, as Mirbel ob-
serves, in Mosses and Ferns. The same writer remarks
that “leaves consist almost-entirely of a plate of this

OF THE CELLULAR INTEGUMENT. 19

si substance, covered on each side by the cuticle. The
‘stems and branches of both annual and perennial
‘ plants are invested with it ; but in woody parts it Is
“ dried up and reproduced continually, such parts only
“having that reproductive power. ‘The old layers
‘remain, are pushed outward by the new ones, and
* form at length the rugged dry dead covering of the
“* old trunks of trees.” |

_ When we come to consider the curious functions of
leaves, we shall find this part to be of the very first
importance. In it the principal changes operated upon
the juices of plants by light and air, and the conse-
quent elaboration of all their peculiar secretions, take
place.

20

CHAPTER V.

OF THE BARK.

Unoper the Cellular Integument we find the Bark,
consisting of but one layer in plants or branches only
one year old, and often not distinguishable from the
wood. In the older branches and trunks of trees, it
consists of as many layers as they are years old, the
innermost being called the ber ; and it is in this layer
only that the essential vital functions are carried on for
the time being, after which it is pushed outwards with
the Cellular Integument, and becomes like that a life-
less crust. ‘These older layers, however, are for sone
time reservoirs of the peculiar secreted juices of the
plant, which perhaps they may help to perfect.

‘In some roots the bark, though only of annual du-
ration, is very thick; as in the Carrot, the red part of
which is all bark. In the Parsnep, though not di-
stinctly coloured, it is no less evident. In the Turnip
it is much thinner, though equally distinct from the
wood or body of the root.

The Bark contains a great number of woody fibres,
running for the most part longitudinally, which give it
tenacity, and in which it differs very essentially from
the parts already described. These woody fibres when
separated by maceration exhibit in general a kind of

OF THE BARK. pm |

net-work, and in many instances great regularity and
beauty of structure. Ina family of plants to which
the Mezereon, belongs, the fibres of the inner bark
have a beautiful white shining appearance like silk.
In one of this tribe, a native of Jamaica, and called
Lace Bark, that part may be separated by lateral ex-
tension into an elegant kind of lace.

In the old bark of the Tir tribe, on the contrary,

nothing of this kind is discernible. The bark of the
Cluster Pine, Puzws Pinaster, some inches in thick-
ness, is separable into thin porous layers, each of them
the production of one season, which do really seem to
be, according to M. Mirbel’s theory, hardened and
dried Cellular Integument; but they are rather per-
haps that vascular part of the Bark which once con-
tained the secreted fluid, or turpentine, so abundant in
this tree.
_ The bark of Oak trees twenty or thirty years old, if
cut and long exposed to the weather, separates into
many fine thin layers, of a similar, though less delicate,
texture to the Lace Bark of Jamaica. All these layers,
in a living state, are closely connected with each other
by the cellular texture which pervades the vegetable
body in general, as well as by transverse vessels neces-
sary for the performance of several functions hereafter
to be mentioned.

In the bark the peculiar virtues or qualities of par-
ticular plants chiefly reside, and more especially in se-
veral of its internal layers nearest to the wood. Here

‘

99 OF THE BARK.

we find in appropriate vessels the resin of the Fir and
Juniper, the astringent principle of the Oak and Wil-
low, on which their tanning property depends, the fine
and valuable bitter of the Peruvian Bark, and the ex-
quisitely aromatic oil of the Cinnamon. The same
secretions do indeed, more or less, pervade the wood
and other parts of these plants, but usually ina irs
concentrated form.

When a portion of the bark of a tree is removed,
the remainder las a power of extending itself laterally,
though very gradually, till the wound is closed. This
is accomplished by each new layer, added to the bark
internally, spreading a little beyond the edge of the —
preceding layer. ‘The operation of closing the wound
goes on the more slow] y, as the wood underneath, from
exposure to the air, has-become dead, and frequently
rotten, proving an incumbrance, which though the
living principle cannot in this instance free itself from,
it has no power of turning to any good. account. If,
however, this dead wood be carefully removed, and
the wound protected from the injuries of the atmo-
sphere, the new bark is found to spread much more
rapidly; and as every new layer of bark forms, as will
be proved in the next chapter, a new layer of wood,
the whole cavity, whatever it may be, is in process of
time filled up. |

This operation of Nature was turned to great ad-
vantage by the late Mr. Forsyth of Kensington gar-
dens, the history of whose experiments is before the

OF THE BARK. 23

public. Under his management many umber trees,
become entirely hollow, were filled with new wood,
and made to produce fresh and vigorous branches ;
and pear-trees, planted in the time of King William,
and become so decayed and knotty as to bear no fruit
worth gathering, were by gradual paring away of the
old wood and bark, and the application of a composi-
tion judiciously contrived to stick close and keep out.
airand wet, restored to such health and strength as to.
cover the garden walls with new branches bearing a.
profusion of fine fruit. These experiments haye passed
under my own actual observation, and I am happy to
bear testimony to the merits of a real lover of useful
science, and one of the most honest and disinterested
men I ever knew.

24,

CHAPTER VI.

ee

OF THE WOOD.

Wuen the bark is removed, we come to the sub-
stance of the wood, which makes the principal bulk of
the trunk or branch of a tree or shrub. | When cut
across, it is found to consist of numerous concentric
layers, very distinct in the Fir, and other European
trees in general. Each of these circular layers is ex-
ternally most hard and solid. They differ however
among themselves in this respect, as well as in their
breadth on the whole. It often happens that all the
layers are broadest towards one side of the tree, so that
their common centre is thrown very much out of the
actual centre of the trunk.

The wood owes its strength and tenacity to innu-
merable woody fibres, and consists of various vessels
running for the most part longitudinally ; some having
a spiral coat, others not. Of these vessels, some in
their youngest state convey the sap from the root to
the extremities of the branches and leaves; others
contain the various peculiar or secreted juices ; others
perhaps contain air. The whole are joined together
by the cellular substance already described.

Linneeus and most writers believe that one of the
abovementioned circular layers of wood is formed every

OF THE WOOD. 95

year, the hard external part being caused by the cold
of winter; consequently, that the exact age of a sound
tree when felled may be known by. counting these
rings. . It has even been asserted that the date of pe-
culiarly severe ‘vinters may be found in the harder
more condensed rings formed at those periods; and
moreover, that the north side of a tree may always be
known by the narrowness and density of the rings on
that side. All this is controverted by Mirbel, chiefly
on the authority of Du Hamel, who nevertheless
scarcely says enough to invalidate the ancient opinion
on the whole. It is very true that there may be occa-
sional interruptions in the formation of the wood, from
cold or fickle seasons, and that in some trees the thin
intermediate layers, hardly discernible in general, which
unite to form the principal or annual ones, may, from
such fluctuation of seasons, become more distinct than
is natural to them. Such intermediate layers are even
found more numerous in some trees of the same species
and age than in others. But as there is always a most
material difference between summer and winter, so I
believe will there always be a clear distinction between
the annual rings of such trees as show them at all.
Trees of hot countries indeed, as Mahogany, and ever-
greens in general, have them but indistinctly marked ;
yet even in these they are to be seen. With regard to
their greater compactness on the north side of a tree,
Du Hamel justly explodes this idea. In fact, there is
most wood formed, and consequently these circles are

£6 OF THE WOOD.

broadest, on the side most favourable to vegetation,
and where there are most branches and leaves. This:
in a solitary tree is generally towards the south ; but it
is easy to perceive the occasional variations which must
arise from local exposure, soil, moisture, and other
causes. |

In some trees, a number of the outermost rings differ
greatly in colour from the innermost, and are called by
workmen the sap. In the Laburnum, the former are
yellow, the latter brown. In the Oak and many other
trees a similar difference, though less striking, is per-
ceptible, and in most the external rings are much less
firm, compact, and durable than the rest, retaining
more vital principle, and more of the peculiar juices of
the plant. Such rings are all comprehended by Du
Hamel under the name of Audbier, alburnum; and he —
rightly observes that this difference often extends to a
greater number of rings on one side of a tree than on
another. It seems that the more vigour there is ina
tree, or side of a tree, the sooner is its alburnum made
perfect wood. By this term, however, is properly un-
derstood only the layer of new unhardened wood of
the present year. When the word alburnum is used
in the following pages, it applies to this part only.

Physiologists have long differed and do still differ
about the origin of the wood. Malpighi and Grew
thought it was formed by the bark, and the best ob-
servations have confirmed their opinion. Hales sup-
posed the wood added a new layer to itself externally

OF THE WOOD. °7

every year. Linnezus had a peculiar notion, thata
new layer of wood was secreted annually from the pith,
and added internally to the former ones. Truth obliges
us to confess that the latter theory is most devoid of
any kind of proof or probability.

Du Hamel, by many experiments, proved the wood
to be secreted or deposited from the innermost part of
the bark or liber. He introduced plates of tinfoil under
the barks of growing trees, carefully binding up their
wounds, and, after some years, on cutting them across,
he found the layers of hew wood on the outside of the
tin. His original specimens I have examined in the
public museum at Paris.

Dr. Hope, the late worthy Professor of Botany at
Edinburgh, instituted an experiment, if possible more
decisive, upon a branch of Willow three or four years
old. The bark was carefully cut through longitudinally
on one side for the length of several inches, so. that it
might be slipped aside from the wood in the form of
a hollow cylinder, the two ends being undisturbed.
The edges of the bark were then united as carefully as.
possible, the wood covered from the air, and the whole
bound up to secure it from external injury. After a
few years, the branch was cut through transversely.
The cylinder of bark was found lined with layers of
new wood, whose number added to those in the wood
from which it had been stripped, made up the number
of rings in the branch above and below the experiment.
For an account of this experiment I am indebted to

98 OF THE WOOD.

Dr. Thomas Hope, the present Chemical Professor at
Edinburgh. |

Du Hamel engrafted a portion of the bark of a
Peach-tree upona Plum. After some time he founda
layer of new wood under the engrafted bark, white
like that of the Peach, and evidently different from the
red wood of the Plum. Moreover, in this and other
experiments made with the same intention, he found
the layers of new wood always connected withthe bark,
and not united to the old wood. Seevhis Piao
des Arbres, vol. 2.29, &c. It deserves also to be men-
tioned, that by performing this experiment of engraft- |
ing a portion of bark at different periods through the
spring and summer, the same accurate observer found
a great difference in the thickness of the layer of new
wood produced under it, which was always less in pro-
portion as the operation was performed later in the
season.

That the bark or /2ber produces wood seems thie
fore proved beyond dispute, but some experiments per-
suaded Du Hamel that in certain circumstances the
wood was capable of producing a new bark. ‘This
never happened in any case but when the whole trunk
of a tree was stripped of its bark. A Cherry-tree
treated in this manner exuded from the whole surface
of its wood in little points a gelatinous matter, which
gradually extended over the whole and became a new
bark, under which a layer of new wood was speedily
formed. Hence Mirbel concludes, vol. 1. 176, that

OF THE WOOD. 29

the alburnum and the wood are really the origin of the
new layers of wood, by producing first this gelatinous
substance, or matter of organization, which he and
Du Hamei call cambium, and which Mirbel supposes
to produce the /éber or young bark, and at the same
time, by a peculiar arrangement of the vascular parts,
the alburnum or new wood. His opinion is strength-
ened by the observation of a tribe of plants to be ex-
plained hereafter, Palms, Grasses, &c. in which there
is no real bark, and in which he finds that the woody
fibres do actually produce the cambiwn. Dr. Hope's
experiment will scarcely invalidate this opinion, be-
cause it may be said the cambium had already in that
case formed the liber.

‘this matter will be better understood when we
come to speak of Mr. Knight's experiments on the
course of the sap. .

30

CHAPTER VII.

OF THE MEDULLA OR PITH.

Tr centre or heart of the vegetable body, within the
wood, contains the AZedulla or Pith. This, in parts
most endowed with life, as roots, and young growing
stems or branches, is a tolerably firm juicy substance,
of an uniform texture, and commonly a pale green or
yellowish colour. Such is its appearance in the young
shoots of Elder in the spring; but in the very same
branches, fully grown, the pith becomes dry, snow-
white, highly cellular, and extremely light, capable of
being compressed to almost nothing. So it appears
likewise in the common Red or White Currant, and
numerous other plants. In many annual ‘stems the
pith, abundant and very juicy while they are growing,
becomes little more than a web, lining the hollow of
the complete stem, as insome Thistles. Many grasses
and umbelliferous plants, as Conium maculatum or
Hemlock, have always hollow stems, lined only with
a thin smooth coating of pith, exquisitely delicate and
brilliant in its appearance. |

Concerning the nature and functions of this part
various opinions have been held.

Du Hamel considered it as merely cellular substance,
connected with what is diffused through the whole

id

OF THE° MEDULLA OR PITH. 31

plant, combining its various parts, but not performing
any remarkable office in the vegetable ceconomy.
Linneus, on the contrary, thought it the seat of life
and source of vegetation ; that its vigour was the main
cause of the propulsion of the branches, and that the
seeds were more especially formed from it. This latter
hypothesis is not better founded than his idea, already

“mentioned, of the pith adding new layers internally
to the wood. © In fact, the pith is soon obliterated in
the trunks of many trees, which nevertheless keep in-
creasing, for a long series of years, by layers of wood
added every year from the bark, even after the heart
of the tree is become hollow from decay.

" Some considerations have led me to hold.a medium
opinion between these two extremes. ‘There is, in
certain respects, an analogy between the medulla of
plants and the nervous system of animals. It is no less
assiduously, protected than the spinal marrow or prin-
cipal nerve. It is branched off and diffused through
the plant, as nerves are through the animal. Hence it
is not absurd to presume that it may, in like manner,
give life and vigour to the whole, though by no means,
any more than nerves, the organ or source of nourish-
‘ment. It is certainly most vigorous and abundant in
young and growing branches, and must be supposed
to be subservient, in some way or other, to their in-
crease. Mr. Lindsay of Jamaica, in a paper read long
ago to the Royal Society, but not published, thought
he demonstrated the medudla in the leaf-stalk of th

32 OF THE MEDULLA OR PITH.

Mimosa pudica, or Sensitive Plant, to be the seat of
irritability, nor can I see any thing to invalidate this
opinion.

Mr. Knight, in the Philosophical Transactions for
1801, p. 348, supposes the medulla may be a reser-
voir of moisture, to supply the leaves whenever an ex-
cess of perspiration renders such assistance necessary,
and he has actually traced a direct communication by

vessels between it and the leaf.‘ Plants,” says that

Ingenious writer, “ seem to require some such reser-
‘“‘ voir; for their young leaves are excessively tender,
“and they perspire much, and cannot, like animals,
‘* fly to the shade and the brook.” |

This idea of Mr. Knight's may derive considerable
support from the consideration of bulbous-rooted
grasses. The common Cats-tail, Phleum pratense,
Engl. Bot. t. 1076, when growing in pastures that are
uniformly moist, has a fibrous root; but in dry situ-
ations, or such as are only occasionally wet, it ac-
quires a bulbous one, whose inner substance is moist
and fleshy, like the pith of young branches of trees.
This is evidently a provision of Nature to guard the
plant against too sudden a privation of moisture from
the soil.

But, on the other hand, all the moisture in the
medulla of a whole branch is, in some cases, too little
to supply one hour's perspiration of a single leaf.
Neither can I find that the moisture of the medulla
varies, let the leaves be ever so flaccid. I cannot but

OF THE MEDULLA OR PITH. 33

incline therefore to the opinion that the medulla is
rather a reservoir of vital energy, even in these bulbous
grasses.

Mr. Knight has shown that the part in question may
be removed without any great injury to a branch, or
at least without immediate injury; but I have had no
opportunity of making any experiments on this parti-
cular subject.

34

CHAPTER VIII.

eee

OF THE SAP-VESSELS, AND COURSE OF THE SAP;
WITIL MR. KNIGHT'S THEORY OF VEGETATION.

Mocu contrariety of opinion has existed among
physiologists concerning the vascular system of plants,
and the nature of the propulsion of the sap through
their stems and branches. Indeed it isa subject upon
~which, till lately, very erroneous ideas have prevailed.

That the whole vegetable body is an assemblage of
tubes and vessels is evident to the most careless ob-
server; and those who are conversant with the micro-
scope, and books relating to it, have frequent oppor-
tunities of observing how curiously these vessels are
arranged, and how different species of plants, especially
trees, differ from each other in the structure and dis-
position of them. Such observations, however, if pur-
sued no further, lead but a little way towards a know-
ledge of the wonderful physiology of vegetables.

In our 2d chapter, mention is made of the general
cellular and vascular texture of plants; we must now
be a little more particular in our inquiries.

That plants contain various substances, as sugar,
gum, acids, odoriferous fluids and others, to which
their various flavours and qualities are owing, is fami-

OF THE SAP-VESSELS. BS

liar to every one; anda little reflection will satisfy us
that such substances must each be lodged in proper
cells and vessels to be kept distinct from each other.
They are extracted, or secreted, from the common juice
of the plant, and called its peculiar or secreted fluids.
Various experiments and observations, to be hereafter
enlarged upon, prove also that air exists in the vege-
table body, and must likewise be contained in appro-
priate vessels. Besides these, we know that plants are
nourished and invigorated by water, which they readily
absorb, and which is quickly conveyed through their
stalks and leaves, no doubt by tubes or vessels on pur-
pose. J'inally, it is observable that all plants, as far as
any experiment has been made, contain acommon fluid,
which at certain seasons of the year is to be obtained
in great quantity, as from vine branches by wounding
them in the spring before the leaves appear, and this
is properly called the sap. It is really the blood of the
plant, by which its whole body is nourished, and from
which the peculiar secretions are made.

The great difficulty has been to ascertain the vessels _
in which the sap runs. Two of the most distinguished
inquirers into the subject, Malpighi and Grew, be-
lieved the woody fibres, which make so large a part
of the vegetable body, and give it consistence and
strength, to be the sap-vessels, analogous to the blood-
vessels of animals, and their opinion was adopted by
Du Hamel. In support of this theory it was justly ob-
served that these fibres are very numerous and strong,

Da

36 OF THE SAP-VESSELS.

running longitudinally, often situated with great uni-
forinity (an argument for their great importance), and
found in all parts of a plant, although in some they are
so delicate as to be scarcely discernible. But Philoso-
phers sought in vain for any perforation, any thing
like a tubular structure In the woody fibres to coun-
tenance this hypothesis, they being divisible almost
without end, like the muscular fibre. This difhieulty
was overlooked, because of the necessity of believing
the existence of sap-vessels somewhere ; for it is evi-
dent that the nutrimental. fluids of a plant must be
carried with force towards certain parts and in certain
directions, and that this can be accomplished by regu-
iar vessels only, not, as Tournefort supposed, by ca-
pillary attraction through a simple spongy or cottony
substance.

I received the first hint of what I now believe to be
the true sap-vessels from the 2d section of Dr. Dar-
wins Phytologia, where it is suggested that what have
been taken for air-vessels are really absorbents destined
to nourish the plant, or, in other words, sap-vessels.
The same idea has been adopted, confirmed by expe-
riments, and carried to much greater perfection, by
Mr. Knight, whose papers in the Philosophical Trans-
actions fur 1801, 1804 and 1805 throw the most bril-
liant light upon it, and, I think, establish no less than
an entirely new theory of vegetation, by which the real
use and functions of the principal organs of plants are
now for the first time satisfactorily explained.

OF THE SAP-VESSELS. 37

In a young branch of a tree or shrub, or in the
stem of an herbaceous plant, are found, ranged round
the centre or pith, a number of longitudinal tubes or
vessels, of a much more firm texture than the adjacent
parts, and when examined minutely, these vessels often
appear to be constructed with a spiral coat. This may
be seen in the young twigs and leaf stalks of Elder,
Syringa, and many other shrubs, as well as in nume-
rous herbaceous plants, as the Peony, and more espe-
cially many of the Lily tribe. Ifa branch or stalk of
any of these plants be partly cut through or gently
broken, and its divided portions slowly drawn asunder,
the spiral coats of their vessels will unroll, exhibiting
a curious spectacle even to the naked eye. In other
cases, though the spiral structure exists, its convolu-
_ tions are scarcely separable at all, or so indeterminate
as to be only marked by an interrupted line of perfora-
tions or slits, as shown by M. Mirbel. Indeed the
very same branches which exhibit these spiral vessels
when young, show no signs of them at a more ad-
vanced period of growth, when their parts are become
more woody, firm, and rigid. No such spiral-coated
vessels have been detected in the bark at any period of
its growth. | |

Malpighi asserts that these vessels are always found
to contain air only, no other fluid; while Grew reports
that he sometimes met with a quantity of moisture in
them. Both judged them to be air-vessels, or, as it
were, the lungs of plants, communicating, as these

38 DR. DARWIN'S EXPERIMENTS.

philosophers presumed, with certain vessels of the leaves
and flowers, of an oval or globular form, but destitute
of a spiral coat. These latter do really contain air,
but it rather appears from experiment that they have
no direct communication with the former. Thus the
tubes in question have always been called air-vessels,
till Darwin suggested their real nature and use*. He
is perhaps too decisive when he asserts that none of
them are air-vessels because they exist in the root,
which is not exposed to the atmosphere. We know
that air acts upon the plant under ground, because
seeds will not vegetate in earth under the exhausted
receiver of an air-pump. Phil. Trans. No. 23. Ido
not however mean to contend that any of these spiral
vessels are air-vessels, nor do I see reason to believe
that plants have any system of longitudinal air-vessels
at all, though they must be presumed to abound in such
as are trausverse or horizontal.

Dr. Darwin and Mr. Knight have, by the most
simple and satisfactory experiment, proved these spiral
vessels to be the channel through which the sap is.
conveyed. ‘The former placed leafy twigs of a com-
mon Fig-tree about an inch deep in a decoction of
madder, and others in one of log-wood. After some
hours, on cutting the branches across, the coloured
liquors were found to have ascended into each branch
by these vessels, which exhibited a circle of red dots

* Du Hamel, indeed, once suspected that they contained “ highly
rarefied sap,” but did not pursue the idea.

MR. KNIGHT'S EXPERIMENTS. $9

round the pith, surrounded by an external circle of
vessels containing the white milky juice, or secreted
fluid, so remarkable in the Fig-tree. Mr. Knight, in a.
similar manner, inserted the lower ends of some cut-
tings of the Apple-tree and Horse-chesnut into an in-
fusion of the skins of a very black grape in water, an.
excellent liquor for the purpose. ‘The result was simi--
lar. Bat Mr. Knight pursued his observations much
further than Dr. Darwin had done; for he traced the
coloured liquid even into the leaves, “ but it had nei-
ther coloured the bark nor the sap between it and the:
wood ; and the medulla was not affected, or at most
was very slightly tinged at its edges.” Phil. Trans.
for 1801, p. 335.

The result of all Mr. Knight’s experiments and re-
marks seems to be, tbat the fluids destined to nourish
a plant, being absorbed by the root and become sap,
are carried up into the leaves by these vessels, called
by him central vessels, from their situation near the
pith. A particular set of them, appropriated to each
leaf, branches off, a few inches below the leaf to which
they belong, from the main channels that pass along
the alburnum, and extend from the fibres of the root
to the extremity of each annual shoot of the plant. As
they approah the leaf to which they are destined,
the central vessels become more numerous, or subdi-
vided. ‘ To these vessels,” says Mr. Knight, “ the
spiral tubes are every where appendages.” p. 336. By
this expression, and by a passage in the following

40 PROPULSION OF THE SAP.

page”, 337, this writer might seem toconsider the spiral
line, which forms the coats of these vessels, as itself a
pervious tube, or else that he was speaking of other
tubes with a spiral coat, companions of the sap-vessels ;
but the plate which accompanies his dissertation, and
the perspicuous mode in which he treats the subject
throughout, prevent our mistaking him on the last
point. In order to conceive how the sap can be so
powerfully conveyed as it is through the vessels in
which it flows, from the root of a tall tree to its highest
branches, we must take into consideration the action of
heat. Weall know that this is necessary to the growth
and health of plants; and that it requires to be nicely
adjusted in degree, in order to suit the constitutions of
different tribes of plants destined for different parts of
the globe. It cannot but act as a stimulus to the living
principle, and is one of the most powerful’ agents of
Nature upon the vegetable as well as animal constitu-
tion. Besides this, however, various mechanical causes
may be supposed to have their effect; as the frequently
spiral or screw-like form of the vessels, in some of
which, when separated from the plant, Malpighi tells
us he once saw a very beautiful undulating motion that
appeared spontaneous. This indeed has not been seen
by any other person, nor can it be supposed that parts

* “ The whole of the fluid, which passes from the wood to the leaf,
seems to me evidently to be conveyed through a single kind of vessel ;
for the spiral tubes will neither carry coloured infusions, nor in the

smallest degree retard the withering of the leaf, when the central ves-
sels are divided.” Knight.

ACTION OF THE SILVER GRAIN. 41

so delicate can, in general, be removed from their
natural situation, without the destruction of that fine
irritability on which such a motion must depend. We
may also take into consideration the agitation of the
vegetable body by winds, which is known by expe-
rience to be so wholesome to it*, and must serve
powerfully to propel the fluids of lofty trees ; the pas-
sage, and evolution perhaps, of air in other parts or
vessels, surrounding and compressing these; and lastly
the action, so ingeniously supposed by Mr. Knight, of
those thin shining plates called the si/ver grain, visible
in oak wood, which pressing upon the sap-vessels, and
being apparently susceptible of quick changes from
variations in, heat or otuer causes, may have a power-
ful effect. “Their restless temper,” says Mr. Knight,
“¢ after the tree has ceased to live, inclines me to be-
lieve that they are not made to be idle whilst it con-
tinues alive.” Phil. Trans. for 1801, p. 344. These
plates are presumed by the author just quoted to be
peculiarly useful in assisting the ascent of the sap
through the alburnum of the trunk or chief branches,
where indeed the spiral coats of the vessels are either |
wanting, or less elastic than in the leaf-stalks and
summits of the more tender shoots.

_ However its conveyance may be accomplished, it is

certain that the sap does reach the parts above men-
) tioned, and there can surely be now as little doubt of

* See Mr. Knight’s experiments in confirmation of this in the Phil.
Trans. for 1803, p. 280.

42 COURSE OF THE SAP.

the vessels in which it runs. That these vessels have
been thought to contain air only, is well accounted for
by Dr. Darwin, on the principle of their not collapsing
when emptied of their sap; which is owing.to their
rigidity, and the elastic nature ot their coats. When
a portion of a stem or branch is cut off, the sap soon
exhales from it, or rather is pushed out by the action
of the vessels themselves: hence they are found empty ;
and for the same reason the arteries of animals were
formerly thought to contain air only. When the sap-
vessels have parted with their natural contents, air and
even quicksilver will readily pass through them, as is
shown by various experiments. Arguments in support
of any theory must be very cautiously deduced from
such experiments, or from any other observations not
made on vegetables in their most natural state and
condition ; and, above all, that great agent the vital
principle must always be kept in view, 1u preference
to mere mechanical considerations.

These to which I give the common name of sap-
vessels, comprehending the common tubes of the al-
burnum, and the central vessels, of Mr. Knight, may
be considered as analogous to the arteries of animals ;
or rather they are the stomach, lacteals and arteries
all in one, for I conceive it to be a great error in
Dr. Darwin to call by this name the vessels which
contain the peculiar secretions of the plant*. These
sap-vessels, no doubt, absorb the nutritious fluids af-

* Phytologia, sect. 2.

~

COURSE OF THE SAP. 43

forded by the soil, in which possibly, as they pass
through the root, some change analogous to digestion
may take place; for there is evidently a great difference,
in many cases, between the fluids of the root, at least
the secreted ones, and those of the rest of the plant ;
and this leads us to presume that some considerable al-
teration may be wrought in the sap in its course through
that important organ. ‘The stem, which it next enters,
is by no means an essential part, for we see many plants
whose leaves and flowers grow directly from the root.
Part of the sap is conveyed into the flowers and fruit,
where various fine and essential secretions are made
from it, of which we shall speak hereafter. By far the
greater portion of the sap is carried into the leaves, of
the great importance and utility of which to the plant
itself Mr. Knight's theory is the only one that gives us

‘any adequate or satisfactory notion. - In those organs

the sap is exposed to the action of light, air and mois-
ture, three powerful agents, by which it is enabled to
form various secretions, at the same time that much
superfluous matter passes off by perspiration. These
secretions not only give peculiar flavours and qualities
to the leaf itself, but are returned by another set of
vessels, as Mr. Knight has demonstrated, into the new
layer of bark, which they nourish and bring to perfec-
tion, and which they enable in its turn to secrete matter
for a new layer of alburnum the ensuing year. It is
presumed that one set of the returning vessels of trees
way probably be more particularly destined to this lat-

44 COURSE OF THE SaP.

ter office, and another to the secretion of peculiar fluids
in the bark. See Phil. Trans. for 1801, p. 337. In the
bark principally, if I mistake not, the peculiar secretions
of the plant are perfected, as gum, resin, &c., each un-
doubtedly in an appropriate set of vessels. From
what has just been said of the office of leaves, we rea-
dily perceive why all the part of a branch above a leaf
or leaf-bud dies when cut, as each portion receives
nourishment, and the means of increase, from the leaf
above it.

By the above view of the vegetable ceconomy, it
appears that the vascular system of plants is strictly
annual, This, of course, is admitted in herbaceous
plants, the existence of whose stems, and often of the
whole individual, is limited to one season ; but it is no
less true with regard to trees. The layer of alburnum
on the one hand is added to the wood, and the lider,
or inner layer of the bark, is on the other annexed to
the layers formed in preceding seasons, and neither
has any share in the process of vegetation for the year
ensuing. Still, as they continue for a long time to be
living bodies, and help to perfect, if not to form, se-
cretions, they must receive some portion of nourish-
ment from those more active parts which have taken
up their late functions.

There is a tribe of plants’ called monocotyledones,
having only one lobe to the seed*, whose growth re-
quires particular mention. To these belongs the na-

* Or rather no true cotyledon at all.

GROWTH OF MONOCOTYLEDONES. 45

tural order of Palms, which being the most lofty, and,
in some instances, the most long-lived of plants, have
justly acquired the name of trees. Yet, paradoxical
as it nay seem, they are rather perennial herbaceous
plants, having nothing in common with the growth of
trees in general. Their nature has been learnedly ex-
plained by M. Desfontaines, a celebrated French bo-
tanist, and by M. Mirbelin his Zraité d’ Anatoie et de
Physiologie Végétales, vol. 1. p.209, and Linneus has
long ago. made remarks to the same purpose. ‘The
Palms are formed of successive circular crowns of
leaves, which spring directly from the root. These
leaves and their footstalks are furnished with bundles
of large sap-vessels and returning vessels, like the leaves
of our trees. When one circle of them has performed
its office, another is formed within it, which being con-
fined below, necessarily rises a little above the former.
Thus successive circles grow one above the other, by
which the vertical increase of the plant is alinost with-
outend. Each circle of leaves is independent of its
predecessor, and has its own clusters of vessels, so that
there can be no aggregatiun of woody circles ; and yet
in some of this tribe the spurious kind of stem, formed
in the manner just described, when cut across shows
something of a circular arrangement of fibres, arising
froin the original disposition of the leaves. The com-
mon orange lily, Zidium bulbiferum, Curt. Mag. t.36,
and white lily, Z. candidum, t. 278, which belong to
the same natural family called monocotyledones, serve

46 OF REVERSED PLANTS.

to elucidate this subject. Their stems, though of only
annual duration, are formed nearly on the same prin-
ciple as that of a Palm, and are really congeries of
leaves rising one above another, and united by their
bases into anapparent stem. In these the spiral coats
of the sap-vessels are very easily discernible.

To conclude this subject of the propulsion of the
sap, it is necessary to say a few words on the power
which the vessels of plants are reported to possess of
conveying their appropriate fluids equally well in either
direction; or, in other words, that it is indifferent
whether a cutting of any kind be planted with its up-
per or lower end in the ground. On this subject also
Mr. Knight has afforded us new information, by ob-
serving that, in cuttings so treated, the returning ves-
sels retain so much of their original nature as to deposit
new wood above the leaf-buds ; that is, in the part of
the cutting which, if planted in its natural position,
would have been below them. It appears, however,
that the sap-vessels must absorb and transmit their sap
in a direction contrary to what is natural; and it is
highly probable, that after some revolving seasons new
returning vessels would be formed in that part of the
stem which is now below the buds. I presume there
can be no doubt that successive new branches would
deposit their wood in the usual position. It is never-
theless by no means common for such inverted cuttings
to succeed atall. An experiment to a similar purpose
is recorded by Dr. Hales, Vegetable Staticks, p. 132,

OF REVERSED PLANTS. 47

t.11, of engrafting together three trees standing in a
row, and then cutting off the communication between
the central one and the earth, so that it became sus-
pended in the air, and was nourished merely through
its lateral branches. ‘The same experiment was suc-
cessfully practised by the late Dr. Hope at Edinburgh
upom three Willows, and in the years 1781, 2, and 3,
I repeatedly witnessed their health and vigour. It was
observed that the central tree was several days later in
coming into leaf than its supporters, but I know not
that any other difference was to be perceived between
them. The tree which wanted the support of the
ground was, some years after, blown down, so that
we have now no opportunity of examining the course
of its vessels, or the mode in which successive layers
of wood were deposited in its branches; but the ex-
periment is easily repeated.

In the weeping variety of the common Ash, now so
frequent in gardens, the branches are completely in-
verted -as to position, yet the returning fluids appear to
run exactly in their natural direction, depositing new
wood, as they are situated, above the buds or leaves ;
and if the end of any branch be cut, all beyond (or
below) the next bud dies; so that in this case gravi-
tation, to which Mr. Knight attributes considerable
power over the returning fluids, Phil. Trans. for 1804,
does not counteract the ordinary course of nature.

48

CHAPTER IX.

eee
OF THE SAP, AND INSENSIBLE PERSPIRATION.

Tue sap of trees, as has been mentioned in the last
chapter, may be obtained by wounding a stem or branch
in spring, just before the buds open, or in the end of
autumn, though less copiously, after a slight frost; yet
not during the frost. In the Palm-trees of hot countries,
it is said to flow from a wound at any time of the year.
It has always been observed to flow from the young
wood or alburnum of our trees, not from the bark ;
which agrees with Mr. Knight's theory.

A common branch of the Vine cut through will yield
about a pint of this fluid in the course of twenty-four
hours. The Birch, Betula alba, aftords plenty of sap ;
some other trees yield but a small quantity. It flows
equally upward and downward from a wound, at least
proportionably to the quantity of stem or branch in
either direction to supply it. Some authors have as-
serted that in the heat of the day it flows most from the
lower part of a wound, and in the cool of the evening
from the upper ; hence they concluded it was ascending
during the first period, and descending in the latter. If
the fact be true, some other solution must be sought;
nor would it be difficult to invent a theory upon this
subject: but we rather prefer the investigation of truth
on more solid foundations. ,

OF THE SAP, AND INSENSIBLE PERSPIRATION. 49

This great motion, called the flowzng, of the sap,
which is to be detected principally in the spring, ‘and
‘slightly in the autumn, is therefore totally distinct from

that constant propulsion of it going on In every grow-
ing plant, about which so much has been said in the
preceding chapter, and which is proved by taking an
entire herb of any kind that has been gathered and
suffered to begin to fade, and immersing its root in
water. By absorption through the sap-vessels it pre-
sently revives, for those vessels require a constant sup-
ply from the root.
_ This flowing of the sap has been thought to demon-
strate a circulation, because, there being no leaves to
carry it off by perspiration, it is evident that, if it were
at these periods running up the sap-vessels with such
velocity, it must run down again by other channels.
As soon as the leaves expand, its motion is no longer
to be detected. ‘The effusion of sap from plants, when
cut or wounded, is, during the greater part of the year,
comparatively very small. Their secreted fluids run
much more abundantly.

I conceive therefore that this flowing is nothing more
than a facility in the sap to run, owing to the peculiar
irritability of the vegetable body at the times above
mentioned; and that it runs only when a wound is
nade, being naturally at rest till the leaves open, and
adinit of its proper and regular coriveyance. Accord-
ingly, ligatures made at this period, which show so
plainly the course of the blood in an animal body,

E

50 OF THE SAP,

have never been found to throw any light upon the
vegetable circulation. ‘This great facility in the sap to
run is the first step towards the revival of vegetation -
from the torpor of winter; and its exciting cause is
heat, most unquestionably by the action of the latter
on the vital principle, and scarcely by any mechanical
operation, or expansive power upon the fluids. The
effect of heat is in proportion to the degree of cold to
which the plant has been accustomed. In forced plants
the irritability, or, to use the words of a late ingenious
author™, who has applied this principle very happily to
the elucidation of the animal ceconomy, excitability, is
exhausted, as Mr. Knight well remarks, and they re-
quire a stronger stimulus to grow with vigour. See
p. 69. Hence vegetation goes on better in the increas-
ing heat of spring than in the decreasing heat of au-
tumn. And here I cannot but offer, by way of illustra-
tion, a remark on the theory advanced by La Cepede,
the able continuator of Buffon, relative to serpents.
That ingenious writer mentions, very truly, that these
reptiles awake from their torpid state in the spring,
while a much less degree of heat exists in the atmo-
sphere than is perceptible in the autumn, when, seem-
ingly from the increasing cold, they become benumbed ;
and he explains it by supposing a greater degree of
electricity in the air at the former season. Dr. Brown's
hypothesis, of their irritability being as it were accu-

* Dr. John Brown, formerly of Edinburgh. See the 14th Section
of Dr, Darwin’s Phytologia on this subject.

f

AND INSENSIBLE PERSPIRATION. 51

mulated during winter, offers a much better solution,
either with respect to the animal or vegetable consti-
tation. For the same reason, it is necessary to apply
warmth very slowly and carefully to persons frozen, or
even chilled only, by a more than usual degree of cold,
which renders them more susceptible of heat, and a
temperate diet and very moderate stimulants are most
safe and useful to the unexhausted constitutions of chil-
dren. The same principle accounts for the occasional
flowing of the sap in autumn aftera slight frost. Such
a premature cold increases the sensibility of the plant
to any warmth that may follow, and produces, ina
degree, the same state of its constitution as exists after
the longer and severer cold of winter. Let me be al-
lowed a further illustration from the animal kingdom.
Every body conversant with labouring cattle must have
observed how much sooner they are exhausted by the
warm days of autumn, when the nights are cold, than
in much hotter weather in summer, and this is surely
from the same cause as the autumnal flowing of the
vegetable sap.

The sap, or lymph, of most plants when collected
in the spring as above mentioned, appears to the sight
and taste little else than water, but it soon undergoes
fermentation and putrefaction. Even that of the Vine
is scarcely acid, though it can hardly be obtained with-
out soine of the secreted juices, which in that plant are
extremely acid and astringent. The sap of the Sugar
Maple, Acer: saccharinum, has no taste, though ac-

EQ

52 OF THE SAP, AND INSENSIBLE PERSPIRATION. |

cording to Du Hamel every 200 fb. of it will afford
10 Ib. of sugar. Probably, as he remarks, itis not col-
lected without an admixture of secreted fluids.

As soon as the leaves expand, insensible perspiration
takes place very copiously, chiefly from those organs,
but also in some degree from the bark of the young
stemor branches. ‘The liquor perspired becomes sen-
sible to us by being collected from a branch introduced
into any sufliciently capacious glass vessel, and proves,
for the most part, a clear watery liquor like the sap,
and subject to similar chemical changes. It is observed
to be uniform in all plants, or nearly so, as well as the
sap, except where odorous secretions transude along
with it. Still there must be a very essential difference
between the original sap.of any plant and its perspira-
tion, the latter no longer retaining the rudiments of
those fine secretions which are elaborated from the
former; but that difference eludes our senses as well
as our chemistry. The perspiration of some plants is
prodigiously great. The large Annual Sunflower, Heli-
anthus annuus, Gerarde Emac. 751. f. 1, according
to Dr. Hales, perspires about 17 times,as fast as the
ordinary insensible perspiration of the human skin.
But.of all plants upon record I think the Cornelian
Cherry, Cornus mascula, is most excessive in this
respect, The quantity of fluid whichjevaporates from
its leaves in the course of twenty-four hours, is said to
be nearly equal to twice the weight of the whole shrub.
Du Hamel Phys. des Arbres, v. 1. 145.

53

CHAPTER X.

ee

OF TUE SECRETED FLUIDS OF PLANTS. GRAFTING.
HEAT OF THE VEGETABLE BODY.

Tue sap in its passage through the leaves and bark
becomes quite a new fluid, possessing the peculiar
flavour and qualities of the plant, and not only yield-
ing woody matter for the increase of the vegetable
body, but furnishing various secreted substances, more
or less numerous and different among themselves.
These accordingly are chiefly found in the bark; and
the vessels containing them often prove upon dissec-
tion very large and conspicuous, as the turpentine-cells
of the Fir tribe. In herbaceous plants, whose stems
are only of annual duration, the perennial roots fre-
quently contain these fluids in the most perfect state,
nor are they, in such, confined to the bark, but depo-
sited throughout the substance or wood of the root, as
in Rhubarb, Rheum palmatum, Linn. fil. Fasc. t. 4,
and Gentian, Gentiana lutea and purpurea, Ger.
Emac. 432, f. 1,2. In the wood of the Fir indeed
copious depositions of turpentine are made, and in that
of every tree more or less of a gummy, resinous, or
saccharine matter is found. Such must be formed by
branches of those returning vessels that deposit the
new alburnum. These juices appear to be matured,

54 RESINOUS SECRETIONS.

or brought to greater perfection, in layers of wood or
bark that have no longer any principal share in the
circulation of the sap.

The most distinct secretions of vegetables require to
be enumerated under several different heads.

Gum or mucilage, a viscid substance of little flavour
or smell, soluble in water, is very general. When su-
perabundant, it exudes from many trees in the form of
large drops or lumps, as in Plum, Cherry, and Peach-
trees, and different species of Mimosa or Sensitive
plants, one of which yields the Gum Arabic, others
the Gum Senegal, &c.

Resin is a substance soluble in Eee ‘and much
more various in different plants than the preceding, as
the Turpentine of the Fir and Juniper, the Red Gum
_of New South Wales, produced by one or more spe-
cies of Eucalyptus, Bot. of N. Holl. t. 13, and the
fragrant Yellow Gum of the same country, see //’hite’s
Voyage, 235, which exudes spontaneously from the
Aanthorrhea Hastile. Most vegetable exudations
partake of a nature between these two, being partly
soluble in water, partly in spirits, and are therefore
called Gum-resins. The milky j juice of the Fig, Spurge,
&c., which Dr. Darwin has shown, and which every
body may see, to be quite distinct from the sap, is,
like animal milk, an emulsion, or combination of a
watery fluid with oil or resin. Accordingly, when suf-
fered to evaporate in the air, such fluids become resins
or gunrresins, as the Gum Euphorbium. In the Ce-

BITTER SECRETION. 55

landine, Chelidonium majus, Engl. Bot. t. 1581, and
some plants allied to it, the emulsion is orange-co-
loured. |

The more refined and volatile secretions of a resi-
nous nature are called Essential Oils, and are often
highly aromatic and odoriferous. One of the most
exquisite of these is afforded by the Cinnamon bark.
They exist in the highest perfection in the perfumed
effluvia of flowers, some of which, capable of combi-
nation with spirituous fluids, are obtainable by distil-
lation, as that of the Lavender and Rose; while the
essential oil of the Jasmine is best procured by immers-
ing the flowers in expressed oil, which imbibes and
retains their fragrance. Such Expressed or Gross Oils,
as they are called, to distinguish them from essential
oils obtained by distillation, are chiefly found in the
seeds of plants. In the pulp of the Olive indeed they
occur in the form of an emulsion, mixed with watery
and bitter fluids, from which the oil easily separates by
its superior lightness. These expressed oils are not
soluble in spirits or water, though by certain interme-
diate substances they may be rendered capable of
uniting with both. | |

The Bitter secretion of many plants does not seem
exactly to accord with any of the joregoing. Some
facts would seem to prove it of a resinous nature, but
it is often perfectly soluble im water. Remarkable in-
stances of this secretion are in the Cinchona officinalis

56 SUGAR.

or Peruvian bark, Lambert Cinchona, t. 1, and every
species, more or less, of Gentian.

Acid secretions are well known to be very general
in plants. Formerly one uniform vegetable or acetous
acid was supposed common to all plants; but the re-
finements of modern chemistry have detected in some
a peculiar kind, as the Oxalic acid, obtained from
Ovalis or Wood Sorrel, and several others. The
astringent principle should seem to be a sort of acid,
of which there are many different forms or kinds, and
among them the tanning principle of the Oak, Wil-
low, &c. .

On the other hand, two kinds of Alkali are furnished
by vegetables, of which the most general is the Vege-
table Alkali, properly so called, known by the name
of Salt of Tartar, or Salt of Wormwood, or more cor-
rectly by the Arabic term Kali. The Fossil Alkali, or
Soda, is most remarkable in certain succulent plants
that grow near the sea, belonging to the genera Che-
nopodium, Salsola,&c. When these plants are culti-
vated ina common soil, they secrete Soda as copiously,
provided their health be good, as in their natural ma-
ritime places of growth. |

Sugar, more or less pure, is very generally found in
plants. It is not only the seasoning of most eatable
fruits, but abounds in various roots, as the Carrot,
Beet, and Parsnip, and in many plants of the grass or
_cane kind besides the famous Sugar Cane, Saccharum

o

VARIETIES OF SECRETIONS. ay

officinarum. ‘There is great reason to suppose Sugai
not so properly an original secretion, as the result of a
chemical change in secretions already formed, either o1
an acid or mucilaginous nature, or possibly a mixture
of both. In ripening fruits this change is most striking,
and takes place very speedily, seeming to be greatly
promoted by heat and light. By the action of frost,
as Dr. Darwin observes, a different change is wrought
in the mucilage of the vegetable body, and it becomes
starch.

A fine red liquor is atforded by some plants, as the
Bloody Dock or Rumex sanguineus, Engl. Bot. t.1533,
the Red Cabbage and Red Beet, which appears only
to mark a variety in all these plants, and not to con-
stitute a specific difference. It is however perpetuated
by seed.

It is curious to observe, not only the various secre-
tions of different plants, or families of plants, by which
they differ from each other in taste, smell, qualities
and medical virtues, but also their great number, and
striking difference, frequently in the same plant. Of
this the Peach-tree offers a familiar example.. The
gum of this treeis mildand mucilaginous. The bark,
leaves and flowers abound with a bitter secretion of a
purgative and rather dangerous quality, than which
nothing can be more distinct from the gum. The fruit
is replete, not only with acid, mucilage and sugar,
but with its own peculiar aromatic and highly volatile

secretion, elaborated within itself, on which its fine

58 FLINTY SECRETION.

flavour depends. How far are we still from under-
standing the whole anatomy of the vegetable body,
which can create and keep separate such distinct and
discordant substances !

Nothing is more astonishing than the secretion of
flinty earth by plants, which, though never suspected
till within a few years, appears to me well ascertained.
A substance is found in the hollow stem of the Bam-
boo, (Arundo Bambos of Linnzus, Nastos of 'Theo-
phrastus,) called ‘Tabaxir or Tabasheer, which is sup-
posed in the East Indies (probably because it is rare
and difficult of acquisition, like the imaginary stone
in the head of a toad) to be endowed with extraordi-
nary virtues. Some of it, brought to England, under-
went a chemical examination, and proved, as nearly
as possible, pure flint. See Dr. Russell’s and Mr.
Macie’s papers on the subject in the Phil. Trans. for
1790 and 1791. Itis even found occasionally in the
Bamboo cultivated in our hot-houses.. But we need
not search exotic plants for flinty earth. I have al-
ready, in speaking of the Cuticle, chapter 3d, alluded
to the discoveries of the late Professor of Chemistry
at the Royal Institution, on this subject. ‘That able
chemist has detected pure ‘flint in the cuticle of various
plants of the family of Grasses, in the Cane (a kind
of Palm) and in the Rough Horsetail, Mguisetum
hyemale, Engl. Bot. t. 915. In the latter it is very
copious, and so disposed as to make a natural file,
which renders this plant useful in various manufac-

ODOUR OF PLANTS. 59

tures, for even brass cannot resist its action. Common
Wheat straw, when burnt, is found to contain a por-
tion of flinty earth in the form of a most exquisite
powder, and this accounts for the utility of burnt straw
in giving the last polish to marble. How great is the
contrast between this production, if it be a secretion,
of the tender vegetable frame, and those exhalations
which constitute the perfume of flowers! One is
among the most permanent substances in Nature, an
ingredient in the primeval mountains of the globe; the
other the invisible untangible breath of a moment!
The odour of plants is unquestionably of a resinous
nature, a volatile essential oil; and several phenomena
attending it well deserve our attentive consideration.
Its general nature is evinced by its ready union with
spirits or oil, not with water; yet the moisture of the
atmosphere seems, In many instances, powerfully to
favour its diffusion. This I apprehend to arise more
from the favourable action of such moisture upon the
health and vigour of the plant itself, thus occasionally
promoting its odorous secretions, than from the fitness
of the atmosphere, so circumstanced, to convey them.
Both causes however may operate. A number of
flowers which have no scent in the course of the day,
smell powerfully in an evening, whether the air be
moist or dry, or whether they happen to be exposed
toit or not. ‘This is the property of some which Lin-
nus has elegantly called flores tristes, melancholy

60 NIGHT-SCENTED FLOWERS.

flowers, belonging to various tribes as discordant as
possible, agreeing only in their nocturnal fragrance,
which is peculiar, very similar and exquisitely delicious,
and in the pale yellowish, greenish, or brownish tint
of their flowers. Among these are Mesembryanthe-
mum noctiflorum, Dill. Elth. t. 206, Pelargonium
triste, Cornut. Canad. 110, and several species akin
to it, Hesperis tristis, Curt. Mag. t.730, Cheiran- |
thus tristis, t.729, Daphne pontica, Andrews's Repos.
t. 73, Crassula odoratissima, ¢.26, and many others*.
A few more, greatly resembling these in the green

* These flowers afford the poet a new image, which is introduced
into the following imitation of Martial, and offered here solely for its
novelty :_

Go mingle Arabia’s gums
With the spices all India yields.

Go crop each young flower as it blooms.
Go ransack the gardens and fields.

Let Pestum’s all-flowery groves
Their roses profusely bestow.
Go catch the light zephyr that roves’
Where the wild thyme and marjoram grow.

Let every pale night-scented flower,
Sad emblem of passion forlorn,
Resign its appropriate hour,
To enhance the rich breath of the morn.

All that art or that nature can find,
Not half so delightful would prove,
Nor their sweets all together combined,
Half so sweet as the breath of my love.

SMELL OF NEW HAY. 61

hue of their blossoms, exhale, in the evening chiefly,
a most powerful lemon-like scent, as Epedendrum en-
sifolium, Sm. Spicil. t. 24, and Chloranthus inconspi-
cuus, Phil. Trans. for 1787, t. 14, great favourites of
the Chinese, who seem peculiarly fond of this scent.
- There are other instances of odorous and aromatic
secretions, similar among themselves, produced by
very different plants, as Camphor. ‘The sweet smell
of new hay is found not only in Anthoxanthum odora-
tum, Engl. Bot. t.647, and some other grasses, but
in Woodruff or Asperula odorata, t. 755, Melilot or
Trifolium officinale, t. 1340, and all the varieties, by
some deemed species, of Orchis militaris, t. 16 and
¢. 1873, plants wilely different from each other in
botanical characters, as well as in colour and every
particular except smell. Their odour has one pecu-
liarity, that it is not at all perceptible while the plants
are growing, nor till they begin to dry. It proceeds
from their whole herbage, and should seem to escape
from the orifices of its containing cells, only when the
surrounding vessels, by growing less turgid, withdraw
their pressure from such orifices. When this scent of
new hay is vehement, it becomes the flavour of bitter
almonds. ‘The taste of syrup of capillaire, given by
an infusion of Orange flowers, is found in the herbage
of Gaultheria procumbens, Andr. Repos. t. 116, and
Spirea Ulmaria, Engl. Bot. t.960, two very diffe-
rent plants.

Some of the above examples show an evident ana-

62 ACRIMONY OF THE ARUM.

logy between the smell and colours of flowers, nor are
they all that might be pointed out. A variety of the
Chrysanthemum indicum*, Curt. Mag. t. 327, with
orange-coloured flowers, was procured from China by
the late Lady Amelia Hume. ‘These faintly agree in
scent, as they do in colour, with the Wall-flower,
Cheiranthus Cheiri; whereas the common purple va-.
riety of the same Chrysanthemum has a totally diffe-
rent and much stronger odour.

There is, of course, still more analogy between the
smell of plants in general and their impression on the
palate, insomuch that we are frequently unable to dis-
criminate between the two. ‘The taste is commonly
more permanent than the smell, but now and then less
so. The root of the Agwm maculatum, Engl. Bot.
t. 1298, for instance, has, when fresh, a most acrid
taste and irritating quality, totally lost by drying, when
the root becomes simply farinaceous, tasteless and
inert ; so that well might learned physicians contrive
the ““ Compound Powder of Arum,” to excuse the
continuance of its use in medicine, unless they had
always prescribed the recent plant.—Many curious
remarks are to be found in Grew relative to the tastes
of plants, and their different modes of affecting our
organs. Anatomy of Plants, p. 279—292. 3

To all the foregoing secretions of vegetables may be
added those on which their various colours depend.
We can but imperfectly account for the green so uni-

* Anthemis artemisiefolia, Willd, Sp. Pl. v. 3. 2184.

COLOURS OF PLANTS. 63

versal in their herbage, but we may gratefully acknow-
ledge the beneficence of the Creator in clothing the
earth with a colour the most pleasing and the least
fatiguing to our eyes. We may be dazzled with the
brilliancy of a flower-garden, but we repose at leisure
on the verdure of a grove or meadow. Of all zreens,
the most delicate and beautiful perhaps is displayed
by several umbelliferous plants under our hedges in
the spring. .

Some of Nature’s richest tints and most elegant
combinations of colour are reserved for the petals of
flowers, the most transient of created beings; and
even during the short existence of the parts they de-,
corate, the colours themselves are often undergoing
remarkable variations. In the pretty little weed |
called Scorpion-grass, J/yosotis scorpioides, Engl. Bot.
¢. 480, and several of its natural order, the flower-buds
are of the most delicate rose-colour, which turns to a
bright blue as they open. Many yellow flowers under
the influence of light become white. Numbers of red,
purple or blue ones are liable, from some unknown
cause in the plant to which they belong, to vary to
white. Such varieties are sometimes perpetuated by
seed, and are almost invariably permanent, if the plants
_be propagated by roots, cuttings, or grafting. Plants
of an acid or astringent nature often become very red
in their foliage by the action of light, asin Rumez,
Polygonum, Epilobium, and Berberis ; and it is re-
inarkable that American plants in general, ag well as

64: : USES OF THE

such European ones as are particularly related to
them, are distinguished for assuming various rich tints
in their foliage of red, yellow, white, or even blue, at
the decline of the year, witness the Gueldet-fose, the
Cornel, the Vine, the Sumach, the .4zalea pontica,
Curt. Mae. t.433, and others. Fruits for the most
part incline to a red colour, apparently from the acid
they contain. I have been assured by a first-rate
chemist that the colouring principle of the Raspberry
is a fine blue, turned red by the acid in the fruit. The
juices of some Fungi, as Boletus bovinus and Agari- —
cus deliciosus, Sowerb. Fungi, t.202, change almost
instantaneously on exposure to the-air, from yellow to
dark blue or green.

These are a few hints only on a subject which opens
a wide field of inquiry, and which, in professedly che-
mical works, is carried to a greater length than I have
thought necessary in a physiological one. See Thom-
son's Chemistry, v.4. and WVilldenow's Principles of
Botany, 229, ° We must ever keep in mind, as we ex-
plore it, that our anatomical instruments are not more
inadequate to dissect the organs of a scarcely distin-
guishable insect, than our experiments are to inves-
tigate the fine chemistry of Nature, over which the
living principle presides.

Before we take leave of the secreted fluids of vege-
tables, a few more remarks upon their direct utility to
the plants themselves may not be superfluous. Mal-
pighi first suggested that these secretions might nou-

SECRETED FLUIDS. 65

rish the plant, and our latest inquiries confirm the
suggestion. Du Hamel compares them to the blood
of animals, and.so does Darwin. But the analogy
seems more plain between the sap, being nearly uni-
form in all plants, and the animal blood; as in that
particular they accord, while the secreted fluids are so
very various. Mr. Knight’s theory confirnis this ana-
logy, at the same time that it establishes the opinion of
Malpighi. The sap returning from the leaf, where it
has been acted upon by tie air and light, forming new
wood, is clearly the cause of the increase of the vege-
table body. But it is not so clear how the resinous,
gummy or other secretions, laid aside, as it were, in
vessels, out of the great line of circulation, can direct-
ly minister to the growth of the tree. I conceive they
may be in this respect analogous to animal fat, a reser-
voir of nourishment whenever its ordinary supplies are
interrupted, as in the winter, or in seasons of great
drought, or of unusual cold. In such circumstances
the mucilaginous or saccharine secretions especially,
perhaps the most general of all, may be abserbed into
the vegetable constitution ; just as fat is into the ani-
mal one, during the existence of any disease that inter-
rupts the ordinary-supplies of food, or interferes with
its due appropriation. It is well known that such
animals as sleep through the winter, grow fat in the
autumm and awake very lean in the spring. Perhaps
the more recent layers of wood in a Plum- or Cherry-
tree, if they could be accurately examined, might be
F

66 GRAFTING.

found to contain a greater proportion of mucilage at
the end of autumn than in the early spring. If these
substances do not nourish the plant, they seem to be
of no use to it, whatever secondary purposes they may
answer in the schemes of Providence. The direct end,
with respect to the plant, of the finer secreted fluids
of its fruit can very well be perceived, as tempting the
appetite of animals, and eccasioning, through their
means, the dispersion ef the seeds; and the perfume
of flowers may attract Insects, and so promote the fer-
tilization of the seed, as will be explained hereafter.
After what has been said we need not waste much
time in considering the hypothesis, advanced by some
philosophers, that the sap-vessels are veins and the re-
turning vessels arteries. ‘This is so far correct, that,
as the chyle prepared by the digestive organs, poured
into the veins and mixed with the blood, is, through
the medium of the heart, sent into the lungs to be
acted upon by the air; so the nutrimental juices of
plants, taken up from the earth, which has been called
their stomach, are carried by the sap-vessels into the
leaves, for similar purposes already mentioned. The
improved sap, like the vivid arterial blood, then pro-
ceeds to nourish and invigorate the whole frame. I
very much doubt, however, if those who suggested the
aboye hypothesis, could have given so satisfactory an
explanation of it.
_ That the secretions of plants are wonderfully con-
stant, appears from the operation of grafting. This

GRAFTING. G7

consists in uniting the branches of two or more sepa-
rate trees, as Dr. Hope’s Willows, see p.47, anda
whole row of Lime-trees in the garden of New Col-
lege, Oxford, whose branches thus make a net- york.
This is called grafting by approach. A more common:
practice, called budding, or inoculating, is to insert a
bud of one tree, accompanied by a portion of its bark,
into the bark of another, and the tree which is thus
engraitedupon is called the stock. By this mode dif-
ferent kinds of fruits, as apples, pears, plums, &c. each
of which is only a variety accidentally raised from
seed, but no further perpetuated in the same manner,
are multiplied, buds of the kind wanted to be propa--
gated being engrafted on so many stocks of a wild
nature. ‘The mechanical part of this practice is de--
tailed in Du Hamel, Miller, and most gardening books,
It is of primaryimportance that the /ider, or young.
bark, of the bud, and that of the stock, should be ac-
curately united by their edges. ‘The air and wet must
of course be excluded.

It is requisite for the success of this operation that
the plants should be nearly akin. Thus the Chionan-
thus virginica, Fringe-tree, succeeds well on the Com-
mon Ash, Lrazinus exvcelsior, by which means it is
propagated in our gardens. Varieties of the same
species succeed best of all; but Apples and Pears, two
different species of the same genus, may be grafted on
one stock. The story of a Black Rose being produced
by grafting a common rose, it is not worth inquiring

FY

68 HEAT OF VEGETABLES.

which, on a black currant stock, is, as far as I can
learn, without any foundation, and is indeed at the
first sight absurd. I have known the experiment tried
tono purpose. ‘The rose vulgarly reported to be so
produced is merely a dark Double Velvet Rose, a
variety, as we presume, of Rosa centifolia. Another
report of the same kind has been raised concerning
the Maltese Oranges, whose red juice has been attri-
buted to their being budded on a Pomegranate stock,
of which I haye never been able to obtain the smallest
confirmation.

Heat can scarcely be denominated a secretion, and.
-yet is undoubtedly a production, of the vegetable as
well as animal body, though in a much lower degree
in the former than the latter. The heat of plants is.
-evinced by the more speedy melting of snow when in
contact with their leaves or stems, compared with
what is lodged upon dead substances, provided the
preceding frost has been sufficiently permanent to cool
those substances thoroughiy. Mr. Hunter appears to
have detected this heat by a thermometer applied in
frosty weather to the internal parts of vegetables newly
opened. It is evident that a certain appropriate por-
tion of heat is a necessary stimulus to the constitution
of every_plant, without which its living principle is
destroyed. Most tropical plants are as etfectually killed
by a freezing degree of cold, as by a boiling heat, and
have nearly the same appearance; which is exemplified
every autumn in the Garden Nasturtium, Zropeolum

FORCING OF PLANTS. ik 69

majus. The vegetables of cold climates, on the con-
trary, support a much greater degree of cold without
injury, at least while in a torpid state ; for when their
buds begin to expand they become vastly more sen-
sible, as is but too frequently experienced in the fickle
spring of our climate. Nor is this owing, as vulgarly
supposed, merely -to the greater power of the cold to
penetrate through their opening buds. It must pene-
trate equally through them in the course of, long and
severe winter frosts, which are never known to injure
bem. The extremely pernicious effects therefore of
cold on opening buds can only be attributed to the in-
creased susceptibility of the vital principle, after it has
been revived by the warmth of spring.

The vegetation of most plants may be accelerated
by artificial heat, which is called forcing them, and
others may, by the same means, be kept in tolerable
health, under a colder sky than is natural to them.
But many alpine plants, naturally buried for months
under a deep snow, are not only extremely impatient
of sharp frosts, but will not bear the least portion of
artificial heat. The pretty Primula marginata, Curt.
Mag. t. 191, if brought into a room with a fire when
beginning to blossom, never opens another bud ; while
the American cowslip, Dedecatheon Meadia, t. 12,
one of the most hardy of plants with respect to cold,
bears forcing admirably well.

Mr. Knight very satisfactorily shows, PAil. Trans.
Jor 1801, 343, that plants acquire habits with regard

7s

70 HEAT OF THE ARUM.

to heat which prove their vitality, and that a forced
Peach-tree will in the following season expand its buds
prematurely in the open air, so as to expose them to
inevitable destruction. See p. 50. A thousand parallel
instances may be observed, by the sagacious gardener,
of plants retaining the habits of their native climates,
which very often proves one of the greatest impedi-
ments to their successful cultivation.

The most remarkable account that has fallen in my
way concerning the production of heat in plants, is
that given by Lamarck in his Lore Francoise, v. 3.
538, of the Common Arum maculatum, Engl. Bot.
t. 1298, (the white-veined variety,) the flower of 7
which, at a certain period of its growth, he asserts to
be, for a few hours, “‘ so hot as to seem burning.”
The learned M. Senebier of Geneva, examining into
this fact, discovered that the heat began when the
sheath was about to open, and the cylindrical body
within just peeping forth ; and that it was perceptible
from about three or four o’clock in the afternoon till
eleven or twelve at night. Its greatest degree was
seven of Reaumur’s scale above the heat of the air,
which at the time of his observation was about four-
teen or fifteen of that thermometer. Such is the ac-
count with which I have been favoured by Dr. Bos-
tock of Liverpool, from a letter of M. Senebier™, dated
Nov. 28, 1796, to M. De la Rive. I have not hither-.

* Itis now published in his Physiologie Végétale, v. 8. 314, where

nevertheless this ingenious philosopher has declared his opinion to be

HEAT OF THE ARUM. 71

to been successful in observing the phenomenon in
question, which however is weil worthy of attention,
and may probably not be confined to this species of
Arum.

rather against the existence of a spontaneous heat in vegetables, and
he explains even the above striking phenomenon upen chemical prin-

ciples, which seem to be very inadequate.

“I
i)

CHAPTER XL.

THE PROCESS OF VEGETATION.—USE OF THE
COTYLEDONS.

W uen a sced is committed to the ground it swells
by the moisture which its vessels svon absorb, and
which, in conjunction with some deeree of heat, sti-
mulates its vital principle. Atmospherical air is also
necessary to incipient vegetation, for seeds in general
will not grow under water, except those of aquatic
plants, nor under an exhatisted receiver ; and modern
chemists have determined oxygen gas, which is always
an ingredient In our atmosphere, to be absorbed by
seeds in vegetation. An experiment is recorded in the
Philosophical ‘Transactions, No. 23, of sowing Let-
tuce-seed in two separate pots, one of which was placed
in the common air, the other in the vacuum of an air-
pump. In the former the young plants rose to the
height of two inches, or more, in a week’s time; in

the other none appeared, till after the pot had been

removed for a similar period into the air agin. Seeds
buried in the ground to a greater depth than is natural
to them do not vegetate, but they often retain their
power of vegetation for au unlimited period. Earth
taken from a considerable depth will, when exposed
to the air, be soon covered with young plants, especially

-

PROCESS OF VEGETATION 73

of Thistles, or of the Cress or Mustard kind, though
no seeds have been allowed to have access to it. If
the ground in old established botanic gardens be dug
much deeper than ordinary, it frequently happens that
species which have been long lost are recovered, from
theirseeds being latent in the soii,as [have been assured
by Mr. Fairbairn of Chelsea garden, and others.

The integuments of the seed, having fulfilled their
destined office of protection, burst and decay. The
young root is the first part of the infant plant that
comes forth, and by an unerring law of Nature it is
sent downwards, to seek out nourishment as well as to
fix the plant to the ground. Insea-weeds, Fuci, Vive
and Conferve, it seems chiefly to answer the latter
purpose. In the Dodder, Cuscu¢a, a parasitical plant,
the original root lasts only till the stems have esta-
blished themselves on some vegetable, on whose juices
they feed by means of other roots or fibres, and then
withers away.

The descent of the root, and the ascent of the leaf-
bud in a contrary. direction, are ingeniously explained
by Dr. Darwin, Phytologia, sect. 9. 3, on the princi-
ple of the former being stimulated by moisture, and
the latter by air, whence each elongates itself where it
is mostexcited. This is perhaps more satisfactory than
any mechanical hypothesis. In whatever position seeds
happen to lie in the earth, the root makes more or les
of a curve in order to shoot downwards. Mr. Hunter
sowed a number of seeds in a basket of earth placed

74 COTYLEDONS.

on an axis, by which their position was a little altered
every day. After the basket had thus made two or
three circumvolutions, the young roots were found to
have formed as many turns in attempting to attain their
natural perpendicular direction. Mr. Knight has ascer-
tained, Phil. Trans. for 1806, that a strong centri-
fugal force applied to vegetating seeds will considerably
divert the root from this direction outwards, while the
stem seems to have a centripetal inclination.

The young root, if it grew in a soil which afforded
no inequality of resistance, would probably in every
case be perfectly straight, like the radical fibres of
bulbous roots in water; but as scarcely any soil is so
perfectly homogeneous, the root acquires an uneven
or zigzag figure.- It is elongated chiefly at its extre-
mity *, and has always, at that part especially, more
or less of a conical or tapering figure.

When the young root has made some progress, the
two lobes, commonly of a hemispherical figure, which
compose the chief bulk of the seed, swell and expand,
and are raised out of the ground by the ascending
stem. These are called the Cotyledons, f. 4. Be-
tween them is seated the Hmbryo or germ of the
plant, called by Linneeus Corcudlum or little heart, in
allusion to the heart of the walnut. Mr. Knight deno-
minates it the germen, but that term is appropriated
to a very different part, the rudiment of the fruit. The

* As may be seen by marking the fibres of Hyacinth roots in water,
or the roots of Peas made to vegetate in wet cotton wool.

OF THE COTYLEDONS. Ves,

expanding Embryo, resembling a little feather, has
been for that reason named by Linneus Plumula; it
soon becomes a tuft of young leaves, with which the
young stem, if there be any, ascends. ‘Till the leaves
unfold, and sometimes after, the cotyledons, assuming
their green colour, perform their functions; then the
latter generally wither. This may be seen in the
Radish, Lupine, Garden Bean, and various umbellife-
rous plants, in all which the expanded cotyledons are
remarkably different from the true leaves. Such is the
general course of vegetation in plants furnished with
two cotyledons, or dicotyledones; but I have already
mentioned a very distinct tribe called monocotyledones ;
see p. 45. These are the Grass and Corn tribe, Palms,
the beautiful Orchis family, and many others. In
these the body of the seed: does not ascend out of
the ground, and they are rather to be considered as
having no cotyledon at all. See Mr. Salisbury’s paper
in the Transactions of the Linnean Society, v. 7, on
the germination of the Orchis tribe. We reserve more
particular remarks on this subject till we examine the
structure of seeds.

Some plants are reckoned by Linnzus to have many
cotyledons, as the Fir and Cypress. But the germina-
tion of these differs in no respect from that of the
generality of dicotyledones. Mr. Lambert, in his
splendid history of the genus Pinus, has illustrated
this peculiarity of structure in the Swiss P. Cembra;
see our tab. 1, fig. 2. In the Dombeya, or Norfolk

760 OF TIE COTYLEDONS.

Island Pine, the cotyledons are very distinctly four :
gee fic...3.

The preservation of the vital principle in seeds is
one of those wondersof Nature which pass unregarded,
from being every day under our notice. Some lose
their vegetative power by being kept cut of the ground
ever so littleta while after they are ripe, and in order
to succced must sow themselves, in their own way,
and at their own time. Others may be sent round the
world through every vicissitude of climate, or buried
for ages deep in the ground, till favourab'e circum-
stances cause them to vegetate. Great degrees of
heat, short of boiling, do not impair the vegetative ©
power of seeds, nor do we know any degree of cold
that has such aneffect. Those who convey seeds from
distant countries, should be instructed to keep them
cry; for, if they receive any damp sufficient to cause
an attempt at vegetation, they necessarily die, because
the process cannot, as they are situated, go on. Ii,
therefore, they are not exposed to so great an artificial
heat as might change the nature of their oily juices,
they can scarcely, according to the experience of Mr.
Salisbury, be kept in too warm a place. By the pre-
servation of many seeds so long under ground, it seems
that long-continued moisture is not in itself ‘fatal to
their living powers; neither does it cause their prema-
ture germination, unless accompanied by some action
of the air.

It is usual with gardeners to keep Melon and Cu-

A

OF THE COTYLEDONS. 77

cumber seeds for a few years, in order that the fu-
ture plants may grow less luxuriantly, and be more
abundant in blossoms and fruit. Dr. Darwin accounts
for this from the damage which the cotyledons may
receive from keeping, by which their power of nou-

rishing the infant plant, at its first germination, is less-
“ened, and it becomes stunted and dwarfish through
its whole duration.

Dr. Thomson, of Edinburgh, in his System of Che-
mistry, vo/. 4. 374, has published a very satisfactory
explanation of one part of the functions of the cotyle-
dons. Several philosophers have discovered that very
soon after the seed begins to imbibe moisture, it gives
out a quantity of carbonic acid gas, even though no
oxygen gas be present. In this case the process stops
here, and no germination takes place. But if oxygen
gas be present, it is gradually absorbed in the same
proportion. At the same time the farina of the cotyle-
dons becomes sweet, being converted into sugar.
‘“‘ Hence it is evident,” says this intelligent writer,
‘‘ that the farina is changed into sugar, by diminishing
its carbon, and of course by augmenting the proportion
of its hydrogen and oxygen*. ‘This is precisely the
process of malting, during which it is well known that
there is a considerable heat evolved. We may con-
clude from this, that during the germination of seeds
in the earth there is also an evolution of a considerable

* This is also the opinion of M. de Saussure, Recherches Chimiques
sur la Végétation, p. 16.

73 OF THE COTYLEDONS.

portion of heat. This indeed might have been ex-
pected, as it usually happens when oxygen gas is ab-
sorbed. So far seems to be the work of chemistry
alone; at least we have no right to conclude that any
other agent interferes; since hay, when it happens to
imbibe inoisture, exhibits nearly the same processes. ”

I conceive the evolution of this heat may powerfully
further the progress of vegetation by stimulating the
vital principle of the embryo, tillits leaves unfold and
assume their functions. It is necessary to observe, that
the above process equally takes place, whether the fa-
-rinaceous particles be lodged in the bulk of the cotyle-
dons themselves, or compose a separate body called by
authors the albwmen, as in grasses and corn.

COALS ER ia.

OF THE ROOT, AND ITS DIFFERENT KINDS.

We begin the description of the completely formed
vegetable by its root, being the basis of all the rest, as
well as the first part produced from the seed. Its
use in general is two-fold; to fix the plant to a com-
modious situation, avd to derive nourishment for its
support. This part is therefore commonly plunged
deeply into the ground, having, as we have already
shown, a natural tendency to grow downwards. In
some cases however, when plants grow on the stems
or branches of others, as the Dodder or Cuscuta, se-
veral Ferns, and a portion of the Orchis tribe, the root
is closely attached to the bark, from which it draws
nourishment, by the under side only, the upper being
bare. ?

The Root consists of two parts, Caudex the body
of the root, and Radicula the fibre. The latter only is
’ essential, being the part which imbibes nourishment.

Reots are either of annual, biennial or perennial
duration. ‘The first belong to plants which live only
one year, or rather one summer, as Barley; the se-
cond to such as are produced one season, and, living
through the ensuing winter, produce flowers and fruit
the following summer, as Wheat; and the third to

80 , OF THE ‘ROOT,

those which live and blossom through many succeed-
ing seasons to an indefinite period, as trees, and many
herbaceous plants. The term biennial is applied to any
plant that is produced one year and flowers another,
provided it flowers but once, whether that event takes
place the second year, as usual, or whether, from un-
favourable circumstances, 1t may happen to be deferred
to any future time. ‘This is often the case with the
Lavatera arborea, Tree Mallow, Engl. Bot. t. 1841,
and some other plants, especially when growing out of
their natural soil or station. Linnzeus justly observes
that, however hardy with respect to cold such plants
may prove before they blossom, they perish at the first
approach of the succeeding winter, nor can any arti-
ficial heat preserve them. ‘This is, no doubt, to be
attributed to the exhaustion of their vital energy by
flowering. Several plants of hot climates, naturally
perennial and even shrubby, become annual in our
gardens, as the 7repeolum, Garden Nasturtium.

In the Turnip, and sometimes the Carrot, Parsnep,
&e., the Caudex or body of the root is above-ground
and bare, becoming as it were a stem. Linneus in-
deed calls the stems of trees ‘‘ roots above ground ;”
but this seems paradoxical and scarcely correct. Per-
haps it would be more accurate to say the caudev is a
subterraneous stem; but we rather presume it has
functions distinct from the stem, analogous, as has
been hinted p. 43, to digestion, at least in those plants
whose stemsare annual though their rootsare perennial.

AND ITS DIFFERENT KINDS. 8I

The fibres of the root, particularly those extremities
of them which imbibe nourishment from the earth, are
in every case strictly annual. During the winter, or
torpid season of the year, the powers of roots lie dor-
mant, which season therefore 1s proper for their trans-
plantation. After they have begun to throw out new
fibres, it is more or less dangerous, or even fatal, to re-
nove them. Very young annual plants, as they form
new fibres with great facility, survive transplantation
tolerably well, provided they receive abundant supplies
of water by the leaves till the root has recovered itself.

Botanists distinguish several different kinds of roots,
which are necessary to be known, not only for botani-
cal purposes, but as being of great importance in agri-
culture and gardening. The generality of roots may
be arranged under the following heads.

1. Radix fibrosa, fig. 5. A Yibrous Root. The most
simple in its nature of all, consisting only of fibres,
either branched or undivided, which convey nou-
rishment directly to the basis of the stem or leaves.
Many grasses, as Poa annua, Engl. Bot. t. 1141,
and the greater part of annual herbs, have this kind
of root. ‘The radical fibres of grasses that grow in
loose sand are remarkably downy, possibly for the
purpose of fixing them more securely to so slippery
a support, or to multiply the surface or points of
absorption in so meagre a source of nutriment. The
fibres of some parasitical plants already alluded to,
G

$2 OF THE ROOT,

0
we

chiefly of the beautiful genus Lpidendrum, are pecu-
liarly thick and fleshy, not only for the purpose of
imbibing the more nourishment, but also to bind

them so strongly to the branches of trees, as to defy

the force of winds upon their large and rigid leaves.

Radiv repens, f.6. A Creeping Root, as in Mint,
Mentha. A kind of subterraneous stem, creeping
and branching off horizontally, and throwing out
fibres as it goes. ‘This kind of root is extremely

- tenacious of life, for any portion of it will grow.

Hence weeds furnished with, it are among the most
troublesome, as the different sorts of Couch-grass,
Triticum repens, Engl. Bot. t. 909, Holcus mollis,
t. 1170, &c.; while, on the other hand, many sea-
side grasses, having such a root, prove of the most
important service in binding down loose blowing
sand, and so resisting the encroachments of the
ocean. These are principally Carex arenaria,
fingl. Bot. t.928, Arundo arenaria, t. 320, and
Elymus arenarius, t. 1672.

Radix fusiformis, f.7. A Spindle-shaped or Taper-
ing Root. Of this the Carrot, Parsnep and Radish
are familiar examples. Such a root is formed, on
the principle of a wedge, for penetrating perpendi-
cularly into the ground. It is common in biennial
plants, but not peculiar to them. © The caudev,-
which is the spindle-shaped part, abounds with the

AND ITS DIFFERENT KINDS. 83

proper secreted juices of the plant, and throws out
numerous fibres or radicles, which are in fact the
real roots, for they alone imbibe nourishment.

4, Radix premorsa, f.8. An Abrupt Root, is natu-
rally inclined to the last-mentioned form, but from
some decay or interruption in its descending point,
it becomes abrupt, or as it were bitten off. Scabiosa
succisa, Devil's Bit Scabious, Engl. Bot. t. 878,
Hedypnois hirta, t.555,and some other Hawkweeds,
have this kind of root, the old opinion concerning
which cannot be better described than in Gerarde’s
Herbal, under the plant first named, p. 726.

« The great part of the root seemeth to be bitten
away : old fantasticke charmers report, that the
divel did bite it for envie, because it is an herbe that
hath so many good vertues, and is so beneficial to
mankinde.”

The malice of the devil has unhap-
pily been so successful that no virtues can now be
found in the remainder of the root or herb.

5. Radix tuberosa, f. 9. A Tuberous or Knobbed
- Root, is of many different kinds. The most genuine
consists of fleshy knobs, various in form, connect-
ed by common stalks or fibres, as in the Potatoe.
Solanum tuberosum, and Jerusalem Artichoke™*,

* A corruption, as I presume, of the Italian marae Girasole Arti-
ciocco, Sun-flower Artichoke, as the plant was first brought from Peru
to Italy, and thence propagated throughout Europe.

G 2

84 OF THE ROOT,

Helianthus tuberosus, Jacq. Hort. Vind. t. 161.
These knobs are reservoirs of nourishment, mois- —
ture, and vital energy. Several of the Vetch or Pea
kind are furnished with them on a smaller scale ;
see Vicia lathyroides, Engl. Bot. t. 30, and several
_ species of Zrifoliwm, either annuals, as glomera-
tum, t. 1063, or perennials, as fragiferum, t. 1050.
—The knobs in these instances are only of annual
duration ; in the, Pgonia, Peony, ¢. 1513, and
Spirea Filipendula, Dropwort, t. 284, they are
perennial.—In the Orchidee of Europe they are
mostly biennial. The root in many of the latter
consists either of a pair of globular or oval bodies,
ae 10, asin Satyrium hircinum, Engl. Bot. t. 34,
Ophrys aranifera, t. 65, and apifera, t. 383; or
are palmate, that is, shaped somewhat like the
human hand, f. 11, as in Orchis maculata, t. 632.
Of these globular or palmate knobs or bulbs one
produces the herb and flowers of the present year,
withering away towards autumn, and the other 1s
reserved for the following season, while in the mean
timea third is produced to succeed the latter. The
knobs of Ophrys spiralis, t. 541, are formed three
or four years before they flower, and their flowering
appears to be occasionally deferred to a more di-
stant period. The root of Satyrium albidum, t.505,
consists of three pair of tapering knobs or bulbs,
f. 12, which flower in succession. On the contrary,
Ophrys monorchis, t.'71, forms its new bulb so late

4

AND ITS DIFFERENT KINDS. 85

that it is not perfected till the autumn immediately
preceding its flowering, and the plant seems to have
but one bulb. Ophrys Nidus avis, t. 48, has clus-
ters of cylindrical knobs, which are formed, and also
wither away, in parcels, each parcel being equiva-
lent to one of the above-mentioned bulbs.

Such of the Orchis tribe as have biennial bulbs
are supposed to be very difficult of cultivation; but
according to the experience of my excellent friend
the late Mr. Crowe, in whose garden I have seen
them many successive years, they are best removed
when in full flower, the earth being cleared com-
pletely away from the roots, which are then to be
replanted in their natural soil previously dried and
sifted. Afterwards they must be well watered. The
bulb for the following year has not, at the flowering
period, begun to throw out its fibres; for after that
happens, it will not bear removal. Satyriem albidum
having, as mentioned above, so many pair of roots,
the growth of some of which is always going on,
has hitherto not been found to survive transplanta-
tion at all. , 3

Tris tuberosa, Sm. I'l. Grac. Sibth. t. 41, has a
root very analogous to these just described, but
I. florentina and I. germanica, t. 39 and 40 of the
same work, have more properly creeping roots,
though so thick and fleshy in their substance, and
so slow in their progress, that they are generally
denominated tuberous.

86 OF THE ROOT,

6. Radix bulbosa. A Bulbous Root, properly so
called, is either solid, 7; 13, as in Crocus, Ivia,
Gladiolus, &c.; tunicate, f. 14, tunicata, composed
of concentric layers enveloping one another as in
Allium, the Onion tribe ; or scaly, f. 15, consisting
of fleshy scales connected only at their base, as in
Lilium, the White or Orange Lily. The two latter
kinds have the closest analogy with leaf-buds. They
are reservoirs of the vital powers of the plant during
the season when those powers are torpid or latent,
and in order to perform the functions of roots, they
first produce fibres, which are the actual roots. The
strict affinity between bulbs and buds appears from
the scaly buds formed on the stem of the Orange
Lily, Lilium bulbiferum, which fall to the ground,
and, throwing out fibres from their base, become
bulbous roots*. The same thing happens in Den-
taria bulbifera, Engl. Bot. t. 309, and Savifraga
cernua, t. 6064.

These two last-mentioned plants however have
scaly roots, like the Toothwort, Lathrea Squamaria,
t. 50, which seem bulbs lengthened out. Whether
they would, in the torpid season of the year, bear
removal, like bulbs, we have no information. If dis-
turbed at other times they are immediately killed.

* T have had scaly buds form even on the flower-stalk of Lachenalia
tricolor, Curt. Mag. t. 82, whilst lying for many weeks between papers
to dry, which, on being put into the ground, have become perfect plants,
though of slow ‘growth.

AND ITS DIFFERENT KINDS. 87

Many plants with solid bulbs are provided by Nature
to inhabit sandy countries, over the face of which,
in the dry season succeeding their flowering, they are
scattered by the winds to a great distance, as hap-
pens to our own Poa bulbosa, Engl. Bot. t. 1071,
as well as to numerous beautiful productions of the
Cape of Good Hope.

7. Radix articulata, or granulata, f. 16. A Jointed or
Granulated Root agrees very much with those de-
scribed in the last section. The O.alis Acetosella,
Wood Sorrel, Hngl. Bot. t. 762, and Savifraga
granulata, White Saxifrage, ¢. 500, are instances of
it. The former has most affinity with scaly bulbs,
the latter with solid ones.

It is evident that fleshy roots, whether of a tuberous
or bulbous nature, must, at all times, powerfully resist
drought. We have already mentioned, p. 32, the ac-
quisition of a bulb in Phleum pratense, Engl. Bot.
t. 1076, whenever that grass is situated ina fluctuating
soil, by which its vital powers are supported while the
fibrous roots are deprived of their usual supplies. In
this state it becomes the Phlewm nodosum of authors ;
but on being removed to a thoroughly wet soil, it re-
sumes the entirely fibrous root, and luxuriant growth,
of Ph. pratense. I have also found Alopecurus geni-
culatus, t. 1250, (an aquatic grass, whose root is natu-
rally fibrous and creeping,) growing with an ovate
juicy bulb on the top ofa dry wall. This variety has

$8 OF THE ROOT,

been taken for the true 4. bulbosus, t. 1249, which
has always bulbs, even in its native marshes. We see
the wisdom of this provision of Nature in the grasses
above mentioned, nor may the cause be totally inex-
plicable. When a tree happens to grow from seed on
a wall, it has been observed, on arriving at a certain
size, to stop for a while, and send down a root to the
ground. As soon as this root was established in the
soil, the tree continued increasing to a large magni-
tude*. Here the vital powers of the tree not being
adequate, from scanty nourishment, to the usual annual
degree of increase in the branches, were accumulated
in the root, which therefore was excited to an extraor-
dinary exertion, in its own natural direction, down-
ward. ‘There is no occasion then to suppose, as some
have done, that the tree had any information of the
store of food at the foundation of the wall, and volun-
tarily sent down its root to obtain it ; nor is it wonder-
ful that the Author of life should provide for it as
effectually as it could for itself, had it really been a
reflecting being. So in the case of the grasses in
question, I presume the herb being in the first instance
starved, by a failure of the nutrimental fluids hitherto
conveyed by the water of the soil, its growth would be
checked, and when checked, the same growth could
not, as we know by observation on vegetation in ge-

* A particular fact of this kind concerning an ash was eommuni-
cated to me by the late Rev. Dr. Walker of Edinburgh. See also

Trans. of Linn, Soc. v. 2 268.

AND ITS DIFFERENT KINDS. 89

neral, be instantaneously renewed. A sudden fresh
supply of foud would therefore cause an accumulation
of vital energy in the root, which would consequently
assume a degree of vigour and a luxuriant mode of
growth not natural to it, and become bulbous. ‘Thus
it acquires a resource against such checks in future,
and the herb is preserved alive, though in a very far
less luxuriant state than when regularly and uniformly
supplied with its requisite nourishment. ‘These are not
solitary instances. Itis well worthy the attention of an
intelligent cultivator to seek them out, and turn them
to his advantage. |

90

CHAPTER XIII.

ee

DIFFERENT KINDS OF STEMS AND STALKS OF
PLANTS.

Liywxvs enumerates seven kinds of Trunks, Stems,
or Stalks of Vegetables. ‘These are necessary to be
known, for botanical distinctions, though some are
more important than others, both in that respect and
in a physiological point of view.

1. Cautis. A Stem properly so called, which bears,
or elevates from the root, the leaves as well as
flowers. The trunks and branches of all trees and
shrubs come under this denomination, as well as of
a great proportion of herbaceous plants, especially
annuals.

The Stem is either simple, as in the White Lily,
or branched, as in most instances. When it is regu-
larly and repeatedly divided, and a flower springs
from each division, it is called caulis dichotomus,
f. 17, a forked stem, as in Chlora perfoliata, Engl.
Bot. t. 60,as well as the common Mouse-ear Chick-
weeds, Cerastium vulgatum, t.'789, and viscosum,
t. 790.

Though generally leafy, a Stem may be partially
naked, or even entirely so in plants destitute of

OF THE STEM. 91

leaves altogether, as the Creeping Cereus, Cactus

flagelliformis, Curt. Mag. t. 17, various exotic

species of Euphorbia or Spurge, and the whole

genus of Stapelia. In Orobanche, it is scaly, f. 18,

squamosus. ,

With respect to mode of growth, the stem is

Erectus, upright, as in Yellow Loosestrife, Lysi-
machia vulgaris, Engl. Bot. t. 761.

Procumbens, procumbent, Wood Loosestrife, L.
nemorum, t. 527.

Repens, creeping, Creeping Loosestrife, L. Num-
mularia, t. 528, and Creeping Crowfoot, Ranun-
culus repens, t. 516.

Adscendens, ascending obliquely without support,
as Panicum sanguinale, t. 849.

Prostratus, prostrate, or Depressus, depressed, when
it lies remarkably flat, spreading horizontally over
the ground, as in Coldenia procumbens; also
Coronopus Ruellii, Swine’s-cress, Engl. Bot.
t. 1660.

Reclinatus, reclining, curved towards the ground,
as in Ficus, the Fig, Rubus, the Bramble, &c.
Radicans, f. 19, clinging to any other body for
support, by means of fibres which do not imbibe -
nourishment, as Ivy, Hedera Helix, Engl. Bot.
t. 1267, Vitisquinquefolia, Sm. Insects of Georgia,
t. 30. Bignonia radicans, Curt. Mag.t.485.—
Linneus, Philosophia Botanica 39, has expressed
this by the term repens, but has corrected it in

OF THE DIFFERENT

his own copy. Still he does not distinguish be-
tween these plants, and those whose stems throw
out real roots, which last only are justly called |
creeping, whether they grow on the ground, like
those above mentioned, or on other plants like
Cuscuta, Dodder, Engl. Bot. t. 55 and 378.
Jee ps ea

Scandens, climbing; either with spiral tendrils for
its support, as the Vine, /’itis, the various species
of Passion-flower, Passiflora cerulea, Curt. Mag.
t. 28, alata, t. 66, &c. and Bryonia dioica, Red-
berried Bryony, Hngl. Bot. t.439; or by adhe-
sive fibres, as in the preceding paragraph.

Volubilis, twining round other plants by its own
spiral form, either from left to right, f.20, sup-
posing the observer in the centre, (or in other
words, according to the apparent motion of the ©
sun,) as the Black Bryony, Zamus communis,
Engl. Bot. t. 91, the Honeysuckles, Lonicera
Caprifolium, t. 799, and Periclymenum, t. 800,
and the Polygonum Convolvulus, t.941; or from
right to left, f- 21, contrary to the sun, as the
Great Bindweed, Convolvulus sepium, t. 313,
the French Bean, Phaseolus vulgaris, Ger. em.
1212, fig. 1, &c.—Figures of plants being some-
times reversed by the engraver, in that case give
a wrong representation of the circumstance in
question, witness Lonicera Periclymenum in
Curtis's Flora Londinensis, fasc. 1. t. 15, and

KINDS OF STEMS. 93

many instances might be pointed out of its not
being attended to at all.

Flagelliformis, long and pliant, like the Common
Jasmine, Jasminum officinale, Curt. Mag. t. 31,
or Blue Box-thorn, Lyczwm barbarum.

Sarmentosus, trailing. A creeping stem, barren of
flowers, thrown out from the root for the purpose
of increase, is called sarmentum or flagellum, a
runner, f. 22, as in the Strawberry, ragaria
wesca, Tingl. Bot. t. 1594. When leafy it is
generally denominated s¢olo, a sucker or scyon,
as in Bugle, Ajuga reptans, t. 489, and Viola
odorata, the Sweet Violet, ¢. 619. When the
stolo has taken root, it sometimes flowers the
first year, see Curt. Lond. fasc. 1. t. 63, but ge-
nerally not till the following season.

Rectus, straight, asin Lilium, the different species
of garden Lily.

Strictus, expresses only a more absolute degree of
straightness.

Laxus or Diffusus, loosely spreading, has a contrary
meaning, as in Bunias Cakile, Sea Rocket, Engl.
Bot. t. 231, and Sedum acre, Biting Stone-crop,
t. 839.

Flevuosus, zigzag, forming angles alternately from
right to left and from left to right, as in Sym-
lax aspera, Ger. em. 859, and many of that
genus, also Statice reticulata, Matted. Sea La-
vender, Hngl. Bot. t. 328. Ina less degree

94 OF THE DIFFERENT

it is not unfrequent. See Atriplex pedunculata,

F252:

Alterne ramosus, alternately branched, as Poly-
gonum minus, t. 1043, Dianthus deltoides, t. 61,
&e. |

Distichus, two-ranked, when the branches spread
in two horizontal directions, as in the Silver Fir,
Pinus picea, Duhamel, Arb. v. 1. t. 1.

Brachiatus, brachiate, or four-ranked, when they
spread in four directions, crossing each other
alternately in pairs; a very common mode of
srowth in shrubs that have opposite leaves, as the
Common Lilac, Syringa vulgaris. “

Ramosissimus, much branched, is applied to a stem
repeatedly subdivided into a great many branches
without order, as that of an Apple- or Pear-tree,
or Gooseberry-bush.

Prolifer, proliferous, shooting out new branches
from the summits of the former ones*, as in the
Scotch Fir, Pinus sylvestris, Lambert's Pinus,
t. 1. and Lycopodium annotinum, Engl. Bot.
t. 1727. This is obsolete, and seldom used.

Determinate ramosus, f. 23, abruptly branched,
when each branch, after terminating in flowers,
produces a number of fresh shoots in a circular
order from just below the origin of those flowers.
This term occurs frequently in the later publica-

/

* Linn. Phil. Bot. sect. 82. 28.

KINDS OF STEMS. 95

tions of Linneus, particularly the second Man-
tissa, but I know not that he has any where ex-
plained its meaning. It is exemplified in Azalea
nudiflora, Curt. Mag. t. 180, Erica Tetralix,
fingl. Bot. t. 1014, many Cape Heaths, and)
other shrubs of the same Natural Order.

Articulatus, jointed, as in Samphire, Salicornia
annua, Eingl. Bot. t. 415, and more remarkably
in the Indian Figs, Cactus Tuna, &c.

In shape the Stem is

Teres, f. 32, round, as in Trollius europeus, Engl.
Bot. t. 28, and Hydrangea hortensis, Sm. Lc.
Pict. ¢. 12.

Anceps, two-edged, as Sisyrinchium striatum, Sim.
Ic. Pict. t. 9. S. gramineum, Curt. Mag. t. 464,
and some of the genus Lathyrus.

Trigonus, or Triangularis, triangular or three-edged,
as Cactus triangularis, Plukenet, t. 20, f. 3.
Triqueter, three-sided, is applied to a stem with 3

flat sides.

Tetragonus, or Quadrangularis, square, as Lamium
album, White Dead-nettle, Engl. Bot. t. 768,
and a multitude of other plants.

Pentagonus, or Quinguangularis, five-sided, as
Asparagus horridus, Cavanilles Ic. t. 136, where
however the character is not well expressed.

When the number of angles is either variable,
or more than five, it is usual merely to describe
the stem as angulosus, angular, except where the

96 ; OF. 'FHE SURFACE

“precise number makes a specific Sania as in
the genus Cactus.

idlatus, f.30, winged, when the angles are extend-
ed into flat leafy borders, as Passiflora alata,
Curt: Mag. t. 66, Lathyrus latiforius, Enel.
Bot. t. 1108, and many others of the Pea kind,
besides several Thistles, as Carduus acanthoides,
t. 973, palustris, t.974, and Centaurea solstitialis,
t. 943.

_ The surface of the Stem is

Glaber, smooth, opposed to all kinds of hairiness or
pubescence, as in Petty Spurge, Luphorbia Peplus,
Engl. Bot. t..959, and numerous plants besides.

Levis, smooth and even, opposed to all roughness
and inequality whatever, as in the last example,
and also Luonymus europaeus, t. 502.

Nitidus, polished, smooth and shining, as Chero-
phyllum sylcestre,t. 752.

Viscidus, viscid, covered with a clammy aria as
Lychnis Viscaria, t. 788.

Verrucosus, warty, like Euonymus verrucosus, Jacq.
Il. Austriaca, t. 49, and Malpighia bang
“Curt. Mag. t: 809.

Papillosus, papillose, covered with soft ii as
- the Ice plant, Wesembryanthemum OTHE
Dill. Elth. t. 180.

“Scaber, rough to the touch from any little rigid

inequalities, opposed to levis, as Caucalis An-

OF THE STEM. 97

thriscus, Engl. Bot. t. 987, Centaurea nigra,
t. 278, and Stellaria holostea, t. 511.

Hispidus, bristly, as Borage, Borago officinalis,
t. 36, and Chara hispida, t.463..

Hirtus, or Pilosus, hairy, as Salvia pratensis, t. 153,
and Cerastium alpinum, t. 472.

Tomentosus, downy, as Geranium rotundifolium,.
t. 157, very soft to the touch.

Villosus, shaggy, as Cineraria integrifolia, t. 152.

Lanatus, woolly, as Verbascum pulverulentum,.
t. 487, V. Thapsus, t. 549, and Santolina mari-
tima, t. 141.

Incanus, hoary, as Wormwood, Artemisia Absin-
thium, t.1230,and Atripler portulacoides, t. 261,
in the former case from close silky hairs, in the:
latter from a kind of scaly mealiness.

Gilaucus, clothed with fine sea-green mealiness
which easily rubs off, as Chlora perfoliata, t. 60,
and Pulmonaria maritima, t. 368.

Striatus, striated, marked with fine parallel lines, as
Ocenanthe jistulosa, t. 363.

Sulcatus, furrowed, with deeper lines, as Smyrnium
Olusatrum, t. 230.

Maculatus, spotted, as Hemlock, Coss macu-
latum, t. 1191.

The spines and prickles of the stem will be explained

hereafter.

Internally the stem is either solidus, solid, as that
of Inula crithmoides, t. 68, and numerous others; or
H

98 OF THE CULM.

cavus, hollow, as in Cineraria palustris, t. 151, as
well-as Hemlock, and many umbelliferous plants be-
sides.
Plants destitute of a stem are called acaules, stem-
less, as Cypripedium acaule, Curt. Mag. t. 192, and
Carduus acaulis, Engi. Bot. t. 161. Such plants,
when they belong to a genus or family generally fur-
nished with stems, as in these instances and Carlina
acaulis, Camer. Epit. 428, are liable from occasional
luxuriance to acquire some degree of stem, but seldom
otherwise*. Pinguicula, Engl. Bot. t. 70 and 145, is
a genus invariably stemless, while Primuda, t. 4, 5, 6
and 513, 1s much less. truly so. The term acaulis
however must never be too rigidly understood, for
logical precision is rarely apphrable to natural pro-
ductions. |
Caulis fasciculatus, a clustered stem, is a disease or
accident, in which several branches or stems are
united longitudinally into a flat broad figure,
crowded with leaves or flowers at the extremity.
_ It occurs in the Ash, several species of Daphne,
Ranunculus, Antirrhinum, &c. In Pisum como-
sum of Rivinus, called the Top-knot Pea, it is
a permanent variely propagated by seed.

2. CuLtmus. A straw or Culm, isthe peculiar Stem

* Neottia acaulis, Exot. Bot. t. 105, proves to have a stem, when in
perfection, and is now ee called N. picta by Dr. Sims in Curt.
Mag. t. 1562. }

OF THE STALK. 99

of the Grasses, Rushes, and plants nearly allied to

them. It bears both leaves and flowers, and its na-

ture is more easily understood than defined. Many
botanists have thought this term rete lek
The Culin is occasionally

Enodis, without joints, as in our common Rushes,

Juncus conglomeratus, Engl. Bot. t. 835, and
" effusus, t. 836;

Articulatus, jointed, as in Agrostis alba, t. 1189,
Aira canescens, t. 1190, Avena strigosa, t. 1266,
and most other grasses;

Geniculatus, bent like the knee, as Alopecurus g oe-
niculatus, t. 1250.

It is either solid or hollow, round or triangular,
rough or smooth, sometimes hairy or downy, scarcely
woolly. I know of no instance of sucha scaly culm as
Linneeus has figured in his Philosophia Botanica, t. 4,
f. 111, nor can I conceive what he had in-view.

3. Scapus, a Stalk, springs from the Root, and bears
the flowers and fruit, but not the leaves. Primula
vulgaris, the Primrose, Engl. Bot. t. 4, and P. veris,
the Cowslip, ¢. 5, are examples of it. In the former
the stalk is simple and single-flowered ; in the latter
subdivided, and many-flowered. It is either naked,
as in Narcissus, Engl. Bot. t. 17, or scaly, as in
Tussilago Farfara, t. 429. In others ot this last
genus, ¢. 430 and 431, the scales become leafy, and
render the Scapus a proper Caulis.

He

100 OF THE FLOWER-STALK.

The Stalk is spiral in Cyclamen, Engl. Bot. t. 548,
and Valisneria spiralis, a wonderful plant, whose his-
tory. will be detailed hereafter.

Linneus believed* thata plant could not be increased
by its Scapus ; which in general is correct, but we have
already recorded an exception, p. 86, in Lachenalia
tricolor. ‘The same great author has observed f that
“a Scapus is only a species of Pedunculus.” The term
might therefore be spared, were it not found very com-
modious in constructing uvat specific definitions of
plants. If abolished, Peduncelus radicalis, a radical
flower-stalk, should be substituted in its room.

4. PEDUNCULUS, the Flower-stalk, springs from the
stem, and bears the flowers and fruit, not the leaves.
Pedicellus, a partial flower-stalk, is the ultimate
subdivision of a general one, as in the Cowslip, and

| Savifraga wnbrosa, Engl. Bot. t. 663. |
The Flower-stalk is
Caulinus, cauline, when it grows immediately out of
the main stem, especially of a tree, as in Averrhoa
Bilimbi, Rumph. Amboin. v. 1. t. 36, the Indian
substitute for our green gooseberries.

Rameus, srowing out of a main branch, as in
Averrhoa Carambola, ibid. t. 35, and Eugenia
malaccensis, vot. Bot. t. 61.

Avillaris, axillary, growing either from the bosom
of aleaf, that is, between it and the stem, as

17 S.in Phil. Bot, 40. | + Ibid.

OF THE FLOWER-STALK. 10]

Anchusa sempervirens, Engl. Bot. t 45, and
Campanula Trachelium, t. 12; or between a
branch and the stem, as Ruppia maritima, t. 136.

Oppositifolius, opposite to a leaf, as Geranium py-
renaicum, t. 405, G. molle, t. 778, and Sium
angustifolium, t. 139.

Iniernodis, proceeding from the intermediate part
of a branch between two leaves, as in Mhretia
wnternodis, L’ Heritier Stirp. t. 24, Solanum ca-
rolinense, Dill. Hort. Elth. t. 259, and indicum,
t..260; but this mode of insertion is rare.

Gemmaceus, growing out of a leaf-bud, as the Bar-
berry, Berberis vulgaris, Engl. Bot. t. 49.

Terminalis, terminal, when it terminates a stem or
branch, as Tulipa sylvestris, t. 63, and Centaurea
Scabiosa, t. 56.

Lateralis, lateral, when situated on the side of a
stem or branch, as rica wagans, t. 3.

Solitarius, solitary, either single on a plant, as in
Rubus Chamemorus, t. 716, or only one in the
same place, as in Antirrhinum spurium, t. 691,
and many common plants.

Ageregati Pedunculi, clustered flow er-stalks, when
several grow together, as in Ver rbascum merum,
Fe 39:

Sparsi, scattered, dipoaed irregularly oyer_ the
plant or branches, as. Linen perenne, t. 40, and
Ranunculus sceleratus, t. 681.

Uniflori, biflori, triflori, &c. bearing one, two,

102 OF THE FROND.

three, or more flowers, of which examples are
needless.

Multiflori, mana ed, as Daphne Laureola,
Fol 19.

When there is no Flpwer-stalk, the Howers are seid
to be Sessi/es, sessile, as in Centaurea Calcitrapa,
t. 125, and the Dodders, ¢. 55 and 378. .

"The subject of inflorescence, or particular modes of

flowering, will be explained im a future chapter.

5. Periotus. The Footstalk, or Leaf-stalk. This
term is applied exclusively to the stalk of a leaf,
which is either simple, as in Ranunculus paxviflorus,
Engl. Bot. t. 120, Sium angustifolium, f. 139, and.
all simple leaves; or compound, as Cortandrum
sativum, t. 67, and Fumaria claviculata, t. 103. 3
In the latter the footstalks end in tendrils, and are
called Petioli cirriferi. .

This part is commonly channelled on the upper side.
Sometimes it is greatlydilated and concave at the base,
as in Angelica sylvestris, t. 1128. — ;

The Footstalk bears the Flower-stalk in Zwrnera
ulmifolia, Linn. Hort. Cliff. t. 10, Menyanthes indica,
Curt. Mag. t. 658, and perpaps Epimedium alpinum,
Lingl. Bot. t. 438.

6. Frons. A Frond. In this the-stem, leaf and fruc-
tification are united, or, in other words, the flowers
and fruit are produced from the leaf itself, as in the

OF THE STIPE. 103

Fera tribe, Scolopendrium vulgare, Engl. Bot.
t. 1150, Polypodium vulgare, t. 1149, Aspidium,
t. 1458—1461, Osmunda regalis, t. 209, &e. It
is also applied to the Zichen tribe, and others, in
which the whole plant is either a crustaceous or a
leafy substance, from which the fructification imme-
diately proceeds. Linnzeus considered Palm-trees
as fronds, so far correctly as that they have not the
proper stem of a tree, see p. 45; but they are rather
perhaps herbs whose staiks bear the fructification.
It must however be observed that the deposition of
wood in ferns, takes place exactly as in palms.

The term frond is now used in the class Crypto-
gamia only.

-
«

7. STIPES, Stipe*, is the stem of a frond, which in
ferns is commonly scaly. See the plates cited in the
last section. ‘The term is likewise applied to the
stalk of a Fungus, as the Common Mushroora,
Agaricus campestris, Sowerby’s Fungi, t. 305,

* Martyn, Language of Botany.

104

CHAPTER XIV.

a

OF BUDS.

Gemma, a Bud, contains the rudiments of a plant,
or of part of a plant, for a while in a latent state, till
the time of the year and other circumstances favour
their evolution. In the bud therefore the vital prin-
ciple is dormant, and its excitability is accumulated.
‘The closest analogy exists between buds and bulbs ;
and indeed the Dentaria bulbifera, Engl. Bot. t. 309,
Lilium bulbiferum, Jacq. Fl. Austr. t. 226, and Ge-
rarde emac. 193, with other similar plants, as men-
tioned p. 86, almost prove their identity.

Buds of trees or shrubs, destined for cold countries,

are formed in the course of the summer In the bosoms
of their leaves, and are generally solitary; but in the
Blue-berried Honeysuckle, Lonicera cerulea, Jacq.
Fl. Austr. append. t. 17, they grow one under another
for three successive seasons, f. 24. The buds of the
Plane-tree, Platanus, Du Hamel Arb. v. 2. 171, are
concealed in the footstalk, which must be removed
before they can be seen, and which they force off by
_ their increase; so that no plant can have more truly and .
necessarily deciduous leaves than the Plane. Shrubs
in general have no buds, neither have the trees of hot
climates. Linneus once thought the presence of buds

\

OF BUDS. 105

might distinguish a tree from a shrub, but he was soon
convinced of there being no real limits between them.
The situation of buds is necessarily like that of the
leaves, alternate, opposite, &c. Trees with opposite
leaves have three buds, those with alternate ones a
solitary bud, at the top of each branch. Du Hamel.
Buds are various in their forms, but very uniform
in the same species or even genus. They consist of
scales closely enveloping each, other, and enfolding
the embryo plant or branch. Externally they have
often an additional guard, of gum, resin or woolliness,
against wet and cold. The Horse Chesnut, sculus
Lippocastanum, now so common with us, though, as
I have learnt from Mr. Hawkins*, a native of Mount
Pindus in Arcadia, is a fine example of large and well-
formed buds, f: 25; and some of the American Wal-
nuts are still more remarkable. |
It has been already remarked, p. 69, that buds re-
sist cold only till they begin to grow: hence, accord-
ing to the nature and earliness of their buds, plants
differ in their powers of bearing a severe or variable
climate. |
Grew is elaborate on the forms of buds, and the
arrangement of the spots apparent within them when
cut transversely, which indicate the number and situ-
ation of their vessels. It was the character of this

\
* See a note on this subject, which Mr. R. P. Knight has honoured

with a place in the second edition of his poem on Landscape.

106 - OF BUDS.

excellent man to observe every thing, without refe-
rence to any theory, and his book is a storehouse of
facts relating to vegetation. Loefling, a favourite pupil
of Linneus, wrote, under the eye of his great teacher,
an essay on this subject, published in the Amenitates
Academice, v. 2, 19 which the various forms of buds,
and the different disposition of the leaves within them,
are illustrated by numerous examples. The Abbé de
Ramatuelle had taken up this subject with great zeal
at Paris, about twenty years ago, but the result of his
inquiries has not reached me.

Dr. Darwin, Phytologia, sect. 9, has many acute ob-
servations on the physiology of buds, but he appears
to draw the analogy too closely between them and the
embryo of a seed, or the chick in the egg. By buds
indeed, as we well know, plants are propagated, and
in that sense each bud is a separate being, or a young
plant in itself; but such propagation is only the exten-
sion of an individual, and not a reprodiction of the

species as by seed. Accordingly, all plants increased
, by buds, cuttings, layers or roots, retain precisely the
peculiar qualities of the individual to which they owe
their origin. If those qualities differ from what are
common to the species, sufficiently to constitute what
is called a variety, that variety is perpetuated through
all the progeny thus obtained. This fact is exemplified
in a thousand instances, none more notorious than the
different kinds of Apples, all which are varieties of the
common Crab, Pyrus Malus, Engl. Bot.t.1795 and

OF BUDS. 107

I cannot but assent to Mr. Knight's opinion, that each

individual thus propagated has only a determinate ex-
-istence, in some cases longer, in others shorter ; from
which cause many valuable varieties of apples and
pears, known in former times, are now worn out, and
others are dwindling away before our eyes. New
varieties of Cape Geraniums, raised from seed in our
greenhouses, are of still shorter duration, and can be
preserved by cuttings for a few successive seasons only ;
yet several of these stand in our botanic works, with
all the importance of real species. Gardeners know
how many of the most hardy perennial herbs require
to be frequently renewed from seed to exist in full
vigour; and though others appear, to our confined
experience, unlimited in that respect, we have many
reasons to believe they are not so. Propagation by
seeds is therefore the only true reproduction of plants,
by which each species remains distinct, and all varia-
‘tions are effaced; for though new varieties may arise
among a great number of seedling plants, it does not
appear that such varieties owe their peculiarities to
any that may have existed in the parent plants. How
propagation by seed is accomplished will be explaimed
in a future chapter, as well as the causes s of some va-
. Yieties produced by that means. _

Mr. Knight in the Philosophical wsdl for
1805, has shown that buds originate from the albur-
num, as might indeed be expected. The trunks and
branches of trees, and the knobs of genuine tuberous

108 OF BUDS.

roots, like the potatoe, are studded with them; in which
respect, as Professor Willdenow judiciously observes,
Principles of Botany, p. 15, such roots essentially
differ from bulbous ones, which last are themselves
simple buds, and produce their shoots, as well as their
ofisets, either from the centre or from the base.

The contents of buds are different, even in different
species of the same genus, as Willows. ‘The buds of
some produce leaves only, others flowers; while in
other species the same bud bears both leaves and
flowers. Different causes, depending on the soil or
situation, seem in one case to generate leaf-buds, in
another flower-buds. ‘Thus the Solandra grandiftora,
Tr. of Linn. Soc. v. 6. 99. t. 6,a Jamaica shrub, was
for a number of years cultivated in the English stoves,
and propagated extensively by cuttings, each plant .
growing many feet in length every season, from abun-
dance of moisture and nourishment, without showing
any signs of fructification. At length a pot of the
Solandra was accidentally left without water in the
dry stove at Kew; and in consequence of this unin-
tentional neglect, the luxuriant growth of its branches
was greatly checked, and a flower came forth at the
extremity of each. By asimilar mode of treatment the
same effect has since frequently been produced. Seve-
ral plants, especially with bulbous roots, which blossom
abundantly in their native soils, have hitherto defied
all the art of our gardeners to produce this desirable
effect; yet future experience may possibly place it

OF BUDS. 109

with'n our reach by some very simple means. In
general, whatever checks the luxuriant production of
leaf-buds, favours the formation of flowers and seeds.
That variety, or perhaps species, of the Orange Lily,
Lilium bulbiferum, which is most prolitic in buds, sel- .
dom forms seeds, or even those organs of the flower
necessary to their perfection. So likewise the seeds of
Mints, a tribe of plants which increase excessively by
roots, have hardly been detected by any botanist; and
it is asserted by Doody in Ray’s Synopsis, that when
the elegant little Ornithopus perpusillus, Engl. Bot.
t. 309, does not produce pods, it propagates itself by
the grains or tubercles of its root, though in general
the root is annual. |

CHAPTER XV.

OF LEAVES, THEIR SITUATIONS, INSERTIONS, SUR-
FACES, AND VARIOUS FORMS.

Fortwm, the Leaf, is a very general, but not univer-
sal, organ of vegetables, of an expanded form, pre-
senting a much greater surface to the atmosphere than
all the other parts of the plant together. Its colour is
almost universally green, its internal. substance pulpy
and vascular, sometimes very succulent, and its upper
and under surfaces commonly ‘differ in hue, as well as
in kind or degree of roughness. ith

Leaves are eminently ornamental to plants from,
their pleasing colour, and the infinite variety as well as
elegance of their forms. ‘Their many ceconomical uses
to mankind, and the importance they hold in the scale
of nature as furnishing food to the brute creation, are
subjects foreign to our present purpose, and need not
here be insisted upon. Their essential importance to
the plant which bears them, and the curious functions
by which they contribute to its health and increase,
will presently be detailed at length. We shall first
explain their different situations, insertions, forms, and
surfaces, which are of the greatest possible use in sy-
stematical botany.

The leaves are wanting in inariy plants, called for

SITUATION AND POSITION OF LEAVES. 111]

that reason plante aphylle, as Salicornia, Engl. Bot.
t.415 and 1691, Stapelia variegata, Curt. Mag. t. 26,
glandulifiora, Evot. Bot. t. 71, and all the species
of that genus. In such cases the surface of the stem
must perform al! their necessary functions.
1. With respect to Situation and Position,

Folia radicalia, radical leaves, are such as spring”
from the root, like those of the Cowslip, Engl.
Bot. t. 5, and Anemone Pulsatilla, t. 51.

_ Caulina,stem-leaves, grow on the stem, as in Paris

quadrifolia, t. 7, Polemonium ceruleum, t. 14,
&c. |

Ramea, branch-leaves, sometimes differ from those
of the main stem, and then require to be distin-
guished from them, as Melampyrum arvense,
$053. | ?

Alterna, f. 21, alternate leaves, stand solitarily on
the stem or branches, spreading in different'direc-
tions, as those of Borage, t. 36, and innumerable
other plants. |

_Sparsa, f. 19, scattered irregularly, as in Genista
tinctoria, t. 44, Lilium chalcedonicum, Curt.
Mag. t. 30, and bulbiferum, t. 36.

Opposita, opposite to eachother, as Savifraga
oppositifolia, Engl. Bot. t. 9, Ballota nigra,
t. 46, &c.

Conferta, clustered, or crowded together, as those
of Trientalis europea, t. 15.

112 SITUATION AND POSITION OF LEAVES.

Bina, only two upon a plant or stem, as in the
Snowdrop, Galanthus nivalis, t.19, Scilla bifolia,
t. 24, and Convallaria majalis, t. 1035.

Terna, three together, as Verbena triphylla, Curt.
Mag.t.367. The plants of Chili and Peru seem
particularly disposed to this arrangement of their
leaves. — |

Quaterna, quina, &c. when 4, 5, of more are so
situated, as in various species of Heath, Erica.

Verticillata, whorled, is used to express several
leaves growing in a circle round the stem, without
a reference to their precise number, as in Aspe-
rula cynanchica, Engl. Bot. t. 33, and odorata,
t. 755, which, with the genus Gadium, and some
others, are for this reason called stellate, star-
leaved plants. Whorled leaves are also found in
Hippuris vulgaris, t.763, and many besides.

Fasciculata, f. 26, tufted, as in the Larch, Pinus
Larix, Lamb. Pin. t.35, the Cedar, and some
others of that genus.

Imbricata, f. 27, imbricated, like tiles upon a house,
as in the common Ling, Erica vulgaris, Engl.
Bot. t. 1013, and Euphorbia paralia, t. 195.

Decussata, f. 28, decussated, in pairs alternately
crossing each other, as Veronica decussata, Curt.
Mag. t. 242, and Melaleuca thymifolia, Exot.
Bot. t. 36. ) ) |

Disticha, f. 29, two-ranked, spreading in two direc-
tions, and yet not regularly opposite at their in-

SITUATION AND POSITION OF LEAVES. 113

sertion, as Pinus canadensis, Lamb, Pin. t. 32,
and the Yew, Taxus baccata, Engl. Bot. t. 746.

Secunda, f. 30, unilateral, or leaning all towards
one side, as Convallaria multiflora, t. 279.

Adpressa, close-pressed to the stem, as Xeranthe-
mum sesamoides, Curt. Mag. t. 425.

Verticalia, perpendicular, both sides at right angles
with the horizon, as Lactuca Scariola, Engl.
Bot. t. 268. |

Erecta, upright, forming a very acute angle with
the stem, as Juncus articulatus, t. 238.

Patentia, spreading, forming a moderately acute
angle with the stem or branch, as Atriplex por-
tulacoides, t. 201.

Forizontalia, horizontal, or patentissima, spreading
in the greatest possible degree, as Gentiana cam-
pestris, t. 237.

Reclinata, inclining downward, as Leonurus Car-
diaca, t. 286.

Recurcva, or reflexra, curved backward, as Erica
retorta, Curt. Mag. t. 362.

Incurva, or inflexa, curved inward, as Erica empe-
trifolia, t. 447.

Obliqua, twisted, so that one part of wr leaf is ver-
tical, the other horizontal, as Fritillaria obliqua,
t. 857, and some of the large Protea. |

Resupinata, reversed, when the upper surface is
turned downward, as Pharus latifolius, Browne's

I

114 INSERTION OF LEAVES.

Jamaica, t. 38, Linn. Mss., and Alstremeria
pelegrina, Curt. Mag. t. 139.

Depressa, radical leaves pressed close to the ground,
as Plantago media, Engl. Bot. t. 1559, and
P. Coronopus, t. 892. The same term applied to
stem-leaves, expresses their shape only, as being
vertically flattened, in opposition to compressa.

Natantia, floating, on the surface of the water, as
Nymphea alba, t. 160, Potamogeton natans,
¢. 1829, and many water plants.

Demersa, immersa, or submersa, plunged under
water, as Potamogeton perfoliatum, t. 168, Hot-.
tonia palustris, t. 364, Lobelia Dortmanna,
t. 140, and the lower leaves of Ranunculus
aquatilis, t. 101, while its upper are folia na-
tantia. .

Emersa, raised above the water, as the upper leaves,
accompanying the flowers, of Myriophyllum ver-
ticillatum, t.218, while its lower ones are de-
mersa.

2. By Insertion is meant the mode in which one part
of a plant is connected with another.
Folia petiolata, \eaves on footstalks, are such as are
furnished with that organ, whether long or short,
~ simple or compound, as Verbascum nigrum,
Engl. Bot. t. 59, Thalctrwm minus, t. 11,
alpinum, t. 262, &c.

INSERTION OF LEAVES. 115

Peltata, f: 31, peltate, when the footstalk is inserted
into the middle of the leaf, like the arm of a
man holding a shield, as in the common Nastur-
tium, Zropeolam majus, Curt. Mag. t. 23,
Drosera peltata, Exot. Bot. t. 41, Cotyledon
Umbilicus, Engl. Bot. t. 325, Hydrocotyle vul-
garis, t.751, and the noble Cyamus Nelumbo,
Exot. Bot. t. 31, 32.

Sessilia, sessile, are such as spring immediately from
the stem, branch or root, without any footstalk,
as in Anchusa sempervirens, Engl. Bot. t. 45,
and. Pinguicula vulgaris, t. 70.

_ Amplexicaulia, f. 32, clasping the stem with their
base, as the upper leaves of Glaucium luteum,
t. 8, Gentiana campestris, t. 237, and Humea
elegans, Evot. Bot. t. 1. ,

Connata, f. 17, connate, united at their base, as
Chiora perfoliata, Engl. Bot. t. 60, whose leaves
are connato-perfoliata.

Perfoliata, f. 33, perfoliate, when the stem runs

through the leaf, as Bupleurum. rotundifolium,
t. 99, and the Uvularia, Exot. Bot, t. 49,50, 51.

Vaginantia, f. 34, sheathing the stem, or each other,
as in most Grasses; see Phleum alpinum, Engl.
Bot. t. 519, and Arundo arenaria, t. 520. The

same character is found in many of the Orchis
tribe, as Satyrium albidum, t. 505.

Equitantia, f. 35, equitant, disposed in two oppo-

site rows and clasping each other by their com-
12

116 FORMS OF LEAVES.

pressed base, as in Narthecium ossifragum, 6.535,
and the genus Iris; also Witsenia corymbosa,
Exot. Bot. t. 68, and Dilatris corymbosa, t. 16.

Decurrentia, f. 36, decurrent, running down the
stem or branch in a leafy border or wing, as
Onopordum Acanthium, Engl. Bot. t. 977, Car-
duus tenuiflorus, t. 412, and many other Thistles,
also the Great Mullein, Verbascum Thapsus,
t. 549, and Comfrey, Symphytum officinale,
COST

Florifera, f. 37, flower-bearing, when We ea crow
out of the disk or margin of any leaf, as in
Ruscus aculeatus, t. 560, Xylophylla latifolia,

and X. falcata, Andr. Repos. t. 331. This is
equivalent to a frond in the class Cryptogamia ;
see p. 103. :
3. With regard to Form, Leaves are either simplicia,
simple, like those of Grasses, Orchises, Lilies, and —

many other plants, Ballota nigra, Engl. Bot. t.46;

and Berberis vulgaris, t. 49; or composita, com- |

pound, as in most Umbelliferous plants, Parsley,

Hemlock, &c.; also Roses, Engl. — t.990— |

992.

In compound leaves the footstalle§ is either simple,
as in the instances last quoted, and Stam angus-
tifolium, t. 139; or compound, like those of
Selinum palustre, t. 229, and Thalictrum majus,
¢.611.—In simple leaves the footstalk, if present,

| FORMS OF LEAVES. 117

must of course be simple, while in compound
ones it must always be present, though not always

_ subdivided.

Simple leaves are either zvtegra, undivided, as those
of Grasses and Orchises ; or /obata, lobed, like
the Vine, the Thistle, most kinds of Cranesbill,
as Geranium pratense, Engl. Bot. t. 404, &c.

Leaves are frequently undivided and lobed on the
same plant, as the Hop, Lingl. Bot. t. 427.

4. The following are the most remarkable forms of
Simple Leaves, considering their outline only.
Orbiculatum, f. 38, a circular or orbicular leaf,
whose length and breadth are equal, and the cir-
cumference an even circular line... Precise ex-
ainples of this are scarcely to be found. Some
species of Piper approach it, and the leaf of
Hedysarum styracifolium is perfectly orbicular,
except a notch at the base. !

Subrotundum, f. 39, roundish, as Pyrola, Engl.
Bot. t. 146, 158 and 213, and many other
plants. :

Ovatum, jf. 40, ovate, of the shape of an egg cut
lengthwise, the base being rounded and broader
‘than the extremity, a very common form of
leaves, as Urtica pilulifera, t. 148, and Vinca
major, t. 514.

Obovatum, f. 41, obovate, of the same yawned with
the broader end uppermost, as those of the Prim-

118 FORMS OF LEAVES.

rose, ¢. 4, and the Daisy, ¢. 424. Linneus at
first used the words obverse ovatum.

Ellipticum, f. 42, or ovale, elliptical or oval, of a
similar form to the foregoing, but of equal breadth
at each end, as in the Lily of the Valley, and
other Convallaria, t. 1035, 279 and 280.

Oblongum, oblong, three or four times longer than
broad. This term is used with great latitude, and
serves chiefly in a specific character to contrast a
leaf which has a variable, or not very decided,
form, with others that are precisely round, ovate,
linear, &c. |

Spatulatum, f. 43, spatulate, of a roundish figure
tapering into an oblong base, as in Silene Otites,
Fl. Brit., Engl. Bot. t. 85.

Cuneiforme, f. 44, wedge-shaped, broad and abrupt
at the summit, and tapering down to the base, as
in Savifraga cuneifolia.

Lanceolatum, f. 45, lanceolate, of a narrow oblong
form, tapering towards each end, very common,

as Tulipa sylvestris, Engl. Bot. ¢. 63, Litho-
spermum purpuro-ceruleum, t. 117, Plantago —
lanceolata, t. 507, many Willows, &e. ,

Lineare, f. 46, linear, narrow with parallel sides, as _
those of mest Grasses ; also Gentiana Pneumo-
nanthe, t. 20, and Narcissus Pseudo-narcissus, —
fee Ws 3

Acerosum, f. 47, needle-shaped, linear and ever-

~ green, generally acute and rigid, as in the Fir

-

FORMS OF LEAVES. 119

Pinus, Juniper, Juniperus communis, t. 1100,
and Yew, Zarus baccata, t. 746. Linnzus
observes, Phil. Bot. 219, that this kind of leaf
has, for the most part, a joint at its union with
the branch.

Triangulare, f. 48, triangular, having three pro-
minent angles, without any reference to their
measurement or direction, as in the genus Che-
nopodium, Cochlearia danica, t. 696, and some
leaves of the Ivy.

Quadrangulare, f. 49, with four angles, as the
Tulip-tree, Ziriodendrum tulipifera, Sm. Ins. of
Georgia, t. 102, Curt. Mag. t.275. on

Quinguangulare, f. 19, with five angles, as some
Ivy leaves, &c.

Deltoides, f. 50, trowel-shaped, or deltoid, having
three angles, of which the terminal one is much
further from the base than the lateral ones,
as Chenopodium Bonus-Henricus, Engl. Bot.
t. 1033, and some leaves of Cochlearia da-
nica. A wrong figure is quoted for this in Phi-
losophia Botanica, which has caused much con-
fusion. |

Rhombeum, f. 51, rhomboid, or diamond-shaped,
approaching to a square, as Chenopodium olidum,
t. 1034, Trapa natans, Camer. Epit. 715, and
Trillium erectum, Curt. Mag. t. 470.

Reniforme, f. 52, kidney-shaped, a short, broad,
roundish leaf, whose base.is hollowed out, as

120 FORMS OF LEAVES.

Asarum europeum, Engl. Bot. t. 1083, and
Sibthorpia europea, t. 649.

Cordatum, f. 53, heart-shaped, according to the
vulgar idea of a heart; that is, ovate hollowed
out at the base, as Tamus communis, t. 91.

Lunulatum, f. 54, crescent-shaped, likea half-moon,
whether the points are directed towards the stalk,
or from it, as Passiflora lunata, Sm. Ic. Pict.
a ° Re

Sagittatum, f. 55, arrow-shaped, triangular, hol-
lowed out very much at the base, as Sagittaria
sagittifolia, Engl. Bot. t. 84, and Rumer Ace-
tosa, t. 197.

Sometimes the posterior angles are cut off, as
in Convolvulus sepium, t. 313.

Hastatum, f. 56, halberd-shaped, triangular, hol-
lowed out at the base and sides, but with spread-
ing lobes, as Rumer Acetosella, t. 1674, An-
tirrhinum Elatine, t. 692, and the upper leaves
of Solanum Dulcamara, t. 565.

Panduriforme, f. 57, fiddle-shaped, oblong, broad
at the two extremities and contracted in the
middle, as the Fiddle Dock, Rumex pmeser ;
i576.

Runcinatum, f. 58, runcinate, or lion-toothed, cut
into several transverse, acute segments, pointing
backwards, as the Dandelion, Leontodon Ta-
ravacum, t. 510.

Lyratum, f. 59, lyrate, or lyre-shaped, cut into

/

FORMS OF LEAVES. 121

several transverse segments, gradually larger to-
wards the extremity of the leaf, which is rounded,
as Hrysimum Barbarea, t. 443. |

Fissum, f. 60, cloven, when the margins of the
fissures and segments are straight, as in the
Gingko-tree, Salisburia adiantifolia.

Bifidum, trifidum, multifidum, &c. express the
number of the segments.

Lobatum, f. 61, lobed, when the margins of the
segments are rounded, as in Anemone Hepatica,
Curt. Mag. t. 10.

Bilobum, trilobum, &c., according to the num-
ber of the lobes. |

Sinuatum, f. 62, sinuated, cut into rounded or wide
openings, as Statice sinuata, t. 71, and Virgilia
helioides, wot. Bot. t. 37.

Partitum, f. 63, deeply divided, nearly to the base,
as Helleborus viridis, Engl. Bot. t. 200.

Bipartitum, tripartitum, multipartitum, ac-
cording to the number of the divisions. :

Laciniatum, f. 64, laciniated, cut into numerous

| irregular portions, as Ranunculus parviflorus,
t. 120, and Geranium columbinum, t. 259.

Incisum,and Dissectum, cut, are nearly synonymous
with the last.

It is remarked by Linnzus that aquatio plants
have their lower, and mountainous ones their
upper, leaves most divided, by which they better
resist the action of the streain in one case, and of

122 TERMINATIONS OF LEAVES.

wind in the other. Probably these actions are in
some measure the causes of such configurations.

Palmatum, J: 65, palmate, cut into several oblong,
nearly equal segments, about half way, or rather
more, towards the base, leaving an entire space
like the palm of the hand, as Passiflora cerulea,
Curt. Mag. t. 28.

Pinnatifidum, f. 66, pinnatifid, cut transversely into

several oblong parallel segments, as in Ipomopsis,
Exot. Bot. t. 13, 14, Bunias Cakile, Engl. Bot.

t. 231, Lepidium didymum, t. 248, petreum,
t.111,and Myriophyllum verticillatum, t. 218.

Bipinnatifidum, f. 67, doubly pinnatifid, as Papaver
Argemone, t. 643, and Eriocalia major, Exot.
Bot. t. 78.

Pectinatum, f. 68, pectinate, is a pinnatifid leaf,
whose segments are remarkably narrow and_pa-
rallel, like the teeth of a comb, as the lower leaves
of Myriophyllum verticillatum, and those of Hot-
tonia palustris, Engl. Bot. t. 364.

Inequale, f. 69, unequal, sometimes called oblique,
when the two halves of the leaf are unequal in

dimensions, aad their bases not parallel, as in -

Eucalyptus resinifera, Exot. Bot. t. 84, and most
species of that genus, as well as of Begonia.

5. The Terminations of Leaves are various.

Lolium truncatum, f. 49, an abrupt leaf, has the.

extremity cut off, as it were, by a transverse

TERMINATIONS OF LEAVES. 123

line, as Liriodendrum tulipifera, Curt. Mag.
ft. 278 |

Premorsum, f. 70, jagged-pointed, very blunt, with
various irregular notches, as in Dr. Swartz’s genus
Aérides, comprehended under the Epidendrum
of Linneus. See E. tessellatum, Roxb. Pl. of
Coromandel, t. 42, and premorsum, t. 43.

Reinrein; f-7), retuse, ending in a broad shallow
notch, as Rumexr digynus, Engl. Bot. t. 910.

Emarginatum, J. 72, emarginate, or nicked, having
a small acute notch at the summit, as the Bladder

Senna, Colutea arborescens, Curt. Mag. t. 81.

. Obtusum, f. 39, blunt, terminating in a segment of
a circle, as the Primrose, Engi. Bot. t.4, Snow-
drop, ¢. 19, Hypericum quadrangulum, t. Ai
and Linum catharticum, t. 382.

Acutum, f. 51, sharp, ending in an acute angle,
which is common to a great variety of plants, as
Ladies’ Slipper, ¢. 1, Campanula Trachelium,
t. 12, and Linum angustifolium, t. 381.

Acuminatum, f. 73, pointed, having a taper or awl-
shaped point, as Arundo Phragmites, t.401, and
Scirpus maritimus, t. 542.

Obtusum cum acumine, f. 74, blunt with a small
point, as Statice Limonium, t. 102.

Mucronatum or Cuspidatum, f. 75, sharp-pointed,
tipped witha rigid spine, as in the Thistles, ¢. 107,
t. 386, &c., Ruscus aculeatus, t. 560, and Mela-
leuca nodosa, Ewot. Bot. t. 35.

124 MARGINS OF LEAVES.

Cirrosum, f. 76, cirrose, tipped witk a tendril, as in
Gloriosa superba, Andr. Repos. t. 129.

6. The different Margins of Leaves are characterized
as follows.

Folium integerrimum, f. 39, an entire leaf, as in the
Orchis and Lily tribe, as well as Polygala vul-—
garis, Engl. Bot. t.76, Daphne Laureola, t. 119,
&c.

This term is opposed to.all kinds of teeth,
notches, or incisions. It regards solely the margin
of a leaf; whereas iztegrum, p. 117, respects its
whole shape, and has nothing to. do with the
margin. English writers who translate the one
entire, and the other very entire, are therefore
incorrect. )

Spinosum, Rae spinous, beset with prickles, as
Carduus lanceolatus, t. 107, and Eryngium cam-
pestre, t.57. The veins are spinous in Solanunt
Pyracantha, Exot. Bot. t. 64, &c.

Inerme, f.71, unarmed, is opposed to spinous.

Ciliatum, f. 78, fringed, bordered with soft parallel
hairs, as Galium cruciatum, Engl. Bot.t. 143.

Cartilagineum, \cartilaginous, hard and horny, as
Sarifraga callosa, Dicks. Dr. Pl. n. 63.

Dentatum, f: 79, toothed, beset with projecting,
horizontal, rather distant teeth of its own sub-
stance, as Atriplex laciniata, Engl. Bot. t. 165,
Eypocheris maculata, t. 225, and. the lower

MARGINS OF LEAVES. 195

leaves of Centaurea Cyanus, t.277 ; also Nym-
phea Lotus, Curt. Mag. t. 797.

Serratum, f. 80, serrated, when the teeth are sharp,
and resemble those of a saw, pointing towards
the extremity of the leaf. Examples of this are
frequent, as Urtica, ¢t. 148 and 1236, Rosa,
t. 992, &c., Comarum palustre, t. 172, and Se-
necio paludosus, t. 650; also Dillenia indica,
Exot. Bot. t. 2. Some leaves are doubly serrated, ©
duplicato-serrata, having a series of smaller ser-
ratures intermixed with the larger, as Mespilus
grandiflora, t. 18, and Campanula Trachelium,
Engl. Bot. t. 12.

Serrulatum, f. 63, minutely serrated, is used when
the teeth are very fine, as in Polygonum amphi-
bium, t. 436, and Empleurum serrulatum, Evot.
Bot. t. 63.

Crenatum, f. 81, notched, or crenate, when the
teeth are rounded, and not directed towards either
end of the leaf, as in Ground-Ivy, Glechoma
hederacea, t. 853, Chrysosplenium, t. 54 and
490, and Stbthorpia europea, t. 649. In Sazi-
Fraga Geum, t. 1561, the leaves are sharply cre-
nate. In the two British species of Salvia, t. 153
and 154, the radical leaves are doubly crenate,
f- 82.

Erosum, f. 83, jagged, irregularly cut or notched,
especially when otherwise divided besides, as in
Senecio squalidus, t. 600.

126 SURFACE OF LEAVES.

~ Repandum, f: 84, wavy, bordered with numerous
minute angles, and small segments of circles al-
ternately, as Menyanthes nympheoides, t. 2 lv
and Inula dysenterica, t. 1115.

Glandulosum, glandular, as Hypericum nipiitenum,
¢. 371, and the Bay-leaved Willow, Salix pen-
tandra.

Revolutum, revolute, when the margin is “beanned or
rolled backwards, as Andromeda polifotia G13,
and Tetratheca glandulosa, Evot. Bot. t. 21.

Linneus seems originally to have applied this
term to the rolling of the whole leaf backwards,
as in Solidago Virgaurea, Engl. Bot. t. 301,
meaning to use the expression margine revolutum
when the margin was intended ; but this latter
case being extremely frequent and the other very

rare, he fell into the practice of using revolutum
simply for the margan.

Involutum, involute, the reverse of the preceding,
as in Pinguicula, t. 70 and 145.

Conduplicatum, folded,when the margins are brought
together in a parallel direction, as in Roscoea
purpurea, Exot. Bot. t. 108, |

7. ‘Terms expressive of different kinds of Surface, ap-
plying equally to the leaf and to the stem, have
_ been already explained, p. 96. To these may be
added the following, chiefly appropriated to leaves.
Punctatum, dotted; either superficially asin Rho-

SURFACE OF LEAVES. <a 127

dodendrum punctatum, Andr. Repos. t. 36, and
Melaleuca linarifolia, Exot. Bot.t.56; or through
the substance, asin Hypericum perforatum, Engl.
Bot. t.295, and the natural order to which the
Orange and Lemon belong. 3

Rugosum, rugged, when the veins are tighter than
the surface between them, causing the latter to
swell into little inequalities, as in various species
of Sage, Salvia. See Flora Greca; also Teu-
crium Scorodonia, Engl. Bot. t. 1543.

Buillatum, blistery, is only a greater degree of the
last,as inthe Garden Cabbage, Brassica oleracea. .

Plicatum, f.85, plaited, when the disk of the leaf,

_ especially towards the margin, is acutely folded
up and down, as in Mallows, and <Alchemilla
vulgaris, Engl. Bot. t. 597, where, however, the
character is but obscurely expressed.

Undulatum, f. 86, undulated, when the disk near
the margin is waved obtusely up and down, as
Reseda lutea, t. 321, and Ixia crispa (more pro-
perly wndulata*) Curt. Mag. t. 599.

Crispum, f. 87, curled, when the border of the leaf
becomes more expanded than the disk, so as to
grow elegantly curled and twisted,which Linnzus
considers as a disease. Malva crispa, Ger. em.
931, is an example of it, and may probably be a
variety of M. verticillata, Jacq. Hort. Vind.
v. 1. t. 40.

* Salish. Hort. 37.

/

128 VEINS AND RIBS OF LEAVES.

Concavum, hollow, depressed in the middle, owing
to a tightness in the border, as Cyamus Nelumbo,
Exot. Bot. t. 32.

Venosum, f. 88, veiny, when the vessels by which
the leaf is nourished are branched, subdivided,
and more or less prominent, forming a network
over either or both its surfaces, as Crate@gus, or
rather Pyrus torminalis, Engl. Bot. t. 298, and
Verbascum Lychnitis, t. 58. |

Nervosum, f. 89, or Costatum, ribbed, when they
extend in simple lines from the base to the point,

as in Cypripedium Calceolus, t. 1, the Corval-
larie, t. 279 and 280, Stratiotes alismoides,

- Exot. Bot. t.15, and Roxburghia wviridiflora,
t. 57. . The greater clusters of vessels are gene-
rally called mervi or cost@, nerves or ribs, and
the smaller vev@,veins, whether they are branched
and reticulated, or simple and parallel.

Avenum, veinless, and Lnerve, ribless, are opposed
to the former.

Trinerve, f. 90, three-ribbed, is chia to a leaf
that has three ribs all distinct from the very base,
as well as unconnected with the margin, in the
manner of those many-ribbed leaves just cited ;
see Blakea trinervis*, Curt. Mag. t. 451.

Basi trinerve, f. 91, three-ribbed at the base, is

_ when the base is cut away close to the lateral ribs,

* Authors incorrectly use the termination ¢rinervius, trinervia, &c.

for the more classical trinervis, trinerve, enervis, encrve.

VEINS AND RIBS OF LEAVES. 129

as in Burdock, Arctium Lappa, iingl. Bot.
#. 1298, Tussilago, t. 430 and 431, andthe
Great Annual Sunfiower.

Triplinerve, f. 92, triply-ribbed, when a pair of
large ribs branch off from the main one above
the base, which is the case in many species of
Sunfiower or Helianthus, Laurus Cinnamomum
and Camphora, as well as Blakea triplinervis,
Aublet Guian. t. 210. ¥

Coloratum, coloured, expresses any colour in a leaf
besides green, as in Arum bicolor, Curt. Mag.
t. 820, Amaranthus tricolor, and others of that
genus, Justicia picta, Hedysarum pictum, Jacq.
Ic. Rar. t. 567, Tradescantia discolor, Sm. Ic.
Pict. t. 10, Pulmonaria officinalis, Engl. Bot.
¢. 118.

Variegatum, variegated, is applied to a sort of
variety or disease, by which leaves become irre-
sularly blotched with white or yellow, lke those
of Striped Grass, drundo colorata, Fl. Brit. ;
as.also the Elder, the Mentha rotundifolia,
fingl. Bot. t. 446, and the Aucuba japonica,
which last is not known in our Pula In its na-
tural green state.

Nudum, naked, implies that a leaf is destitute of
all kinds of clotiing or hairiness, as in the genus
Orchis. Nudus applied to a stem means that it
bears no leaves, and to a flower that it bas no
calyx. |

K

ee SUBSTANCE, ETC. OF LEAVES.

8. ‘The following terms express the substance, pecu-
liar configuration, or any other remaining circum-
stances of leaves, not already explained.

Teres, f. 93, cylindrical, as those of Conchium —
vibbosum, White's Voyage, t. 92, f. 2;° see
Cavanilles Icones, t. 533 and 534.

Semicylindraceum, f. 94, semicylindrical, flat on
one side, as Salsola fruticosa, Engl. Bot. t.635,
and Chenopodium maritimum, t. 633.

Subulatum, f. 95, awl-shaped, tapering from’a thick-
ish base to a point, as Salsola Kali, t. 634.

Tubulosum, tabular, hollow within, as Allium Cepa,
the Common Onicn. The leaf of Lobelia Dort-
manna, Engl. Bot. t. 140, is very peculiar in
consisting of a double tube, f- 96.

Carnosum, f. 98, fleshy, of a thick pulpy substance,
as in all those called succulent plants, Crassula
lactea, Evot. Bot. t. 33, Aloe, Sedum, Mesem-
bryanthemum, &c. See Sempervivum tectorum,
Engl. Bot. t. 1320. | |

Gibbum, gibbous, swelling on one. side or both,
from excessive abundance of pulp, as Aloe retusa,
Curt. Mag. t. 455.

Compressum, f. 98, compressed, flattened laterally,
as Mesembryanthemum uncinatum, Dill. Elth.
t. 193, and acinaciforme, t. 211.

Depressum, depressed, flattened vertically, as MW.
linguiforme, t. 183—185. See p. 114.

Canaliculatum, f. 97, channelled, having a longi-

SUBSTANCE, ETC. OF LEAVES. 151

tudinal furrow, as JZ. pugioniforme, t. 210,
Plantago maritima, Engl. Bot. t. 175, and
Narcissus poeticus, t. 275.

Carinatum, keeled, when the back is longitudinally
prominent, as Narcissus biflorus, t. 276.

Ensiforme, sword-shaped, is a two-edged leaf, ta-
pering to a point, slightly convex on both sur-
faces, neither of which can properly be called
upper or under, as in most of the genus /rvs. See
Ciat. Mag.© t. 671, t. 9, &c.; and Fl Gree:
¢. 39 and 40.

Anceps, two-edged, is much the same as the last.

Acinaciforme, cimeter-shaped, compressed, with one
thick and straight edge, the other thin and curved,
as Mesembryanthemum acinaciforme above men-
tioned.

Dolabriforme, f. 98, hatchet-shaped, compressed,
with a very prominent d lated keel, and a cylin-
drical base, as AZ. dolabriforme, Dill. Elth.t. 191,
Curt. Mag. t. 32.

These two last terms might well be spared, as they
seem contrived only for the plants in question, and in-
deed are not‘essentially distinct from each other.

Trigonum, f. 99, three-edged, having three longi-
tudinal sides and as many angles, like MZ. deltoides,
Dill. Elth. t. 195, Linn. Phil. Bot.t.1, f. 58.
Linneus has erroneously referred to this figure to
illustrate his term deltoides; misled, as it should
seem, by the name of the plant to which it be-

K &

132 SUBSTANCE, ETC. OF LEAVES.

lon Os

iss

see Pp. 119, and alludes to the outline of a flat

; but his definition is foreign to the purpose,

leaf. |

Triguetrum ditters from trigonum only in being
used by Linnaeus for a three-sided awl-shaped
leaf, as WM. emarginatum, Dill. Llth. t. 197;

jf. 250, and bicelorum, t. 202, also Sarifraga
, burseriana.

Zetragonum, f. 100, four-edged, having four pro- —
minent angles, as Zris tuberosa, Fl. Gree. t. 41.

Lingulatum, tongue-shaped, of a thick, oblong, -
blunt figure, generally cartilaginous at the edges,
as Mesembryanthemum linguiforme, Dendrobium
linguiforme, Evot. Bot. t. 11, and several species
of Savifraga, as S. mutata, Curt. Mag. t. 351,
S. Cotyledon, &c.

Membranaceum, membranous, of a thin and pliable
texture, as in Aristolochia Sipho, t. 534, Rubus
odoratus, t. 323, Magnolia purpurea, t. 390, &e.

Coriaceum, leathery, thick, tough and somewhat
rigid, as Magnolia grandiflora, «xd Hydrangea
hortensis, Sm. Ic. Pict. t. 12, Curt, Mag. t.438.

Sempervirens, evergreen, permanent through one, —
two, or more winters, so that the branches are
never stripped, as the Ivy, the lir, the Cherry
Laurel, the Bay, &c.

Deciduum, deciduous, falling. off at the approach of
winter, as 1n most Baccteas trees and shrubs. —

Alienatum, f. 101, alienated, when the first leaves

SUBSTANCE, ETC. OF LEAVES. 133

of a plant give place to others totally different
from them and from the natural habit of the
genus, as in many Mimose of New Holland ; see
M. on i Curt. Mag. t. 110, and myrti-
fotia, t. salso Lathyrus Nissolia, Engl. Bot.
rete bel eas

Cucullatum, f. 102, hooded, when the edges meet
in the lower part, and expand in the upper, as
those of the curious genus Sarracenia. See
Curt. Mag. t. 780 and 849, and S. adunca,
Evot. Bot. t. 53.

Appendiculatum, J. 103, furnished with an addi-
tional organ for some particular purpose not es-
sential to a leaf, as Dionea muscipula, Curt.
Mag. t. 785, cultivated very successfully by Mr.
Salisbury, at Brompton, whose leaves each ter-
minate in a pair of toothed irritable lobes, that
close over and imprison insects ; or NVepenthes
distillatoria, Rumph. Amboin. 0. 5. t. 59, f. 2;
the leaf of which bears a covered pitcher, full of
water. Aldrovanda vesiculosa, and our Utricu-
larie, Engl. Bot. t. 253, 254, have numerous
bladders attached to the leaves, which seem to
secrete alr, and float the plants.

Many of the preceding terms applied to leaves are
occasionally combined, to express a form between the
two, as ovato-lanceolatum, lanceolate inclining to ovate,
or elliptivo-lanceolatum, like the Privet, Engl. Bot.
t.'764. When shape, or any other character, cannot
be precisely defined, sb is prefixed to the term used,

134 COMPOUND LEAVES.

as subrotundum, roundish, swbsessile, not quite desti-
tute ofa Aphis to which is equivalent sebpetiolatum,
obscurely stalked. By the judicious use of such means,
all necessary precision is attained. It is to be wished
that authors were always uniform and consistent, at
least with themselves, inthe application of terms; butas
Linneus, the father of accurate botanical phraseology,
very frequently misapplies his own terins, itis perhaps
scarcely to be avoided. I have observed botanists most
critical in theory, to be altogether deficient in that cha-
racteristic phraseology, that power of defining, which
bears the stamp of true genius, and which renders: the
works of Linnus so luminous in despite of incidental
errors. Perhaps no mind, though ever so intent on
the subject, can retain all the possible terms of descrip-
tion and their various combinations, for ready use at
any given moment. There are few natural objects to
which a variety of terms are not equally applicable in
description, so that no two writers would exactly agree
in their use. Neither is Nature herself so constant as
not perpetually to elude our most accurate research.
Happy is that naturalist who can seize at a glance
what is most characteristic and permanent, and define
all that is essential, without trusting to fallacious,
though ever so specious, distinctions !

9. Folia composita, compound leaves, consist of two
or any greater number of foliola, leaflets, connected
by acommon footstalk.

Lolium articulatum, f. 104, a jointed leaf, is when

/

COMPOUND LEAVES. 135

one leaflet, or pair of leaflets, grows out of the
summit of another, with a sort of joint, as in
Fagara tragodes, Jacq. Amer. t..\4.

Digitatum, f. 22, digitate or fingered, when several
ieaflets proceed from the summit of a common
footstalk, as Potentilla verna, Lingl. Bots) 37,
reptans, t. 862, and Alchemilla alpina, t. 244.

Binatum, f. 105, binate, is a fingered leat consist-
ing of only two leailets, as in Zygophyllum, Curt.

jj dMag..t..372:

_ Ternatum, f. 106, ternate, consists of three leaflets,
as Fagonia cretica, t. 241, and the genus 77rifo-
lium, Trefoil. See Engl. Bot. t. 190, &c.

Quinatum, quinate, of five leaflets, as Potentilla
alba, t. 1384, reptans, t. 862, &e.

Pinnatum, pinnate, when several leaflets proceed
laterally from one footstalk, and imitate a pinna-
tifid leaf, p. 122. ‘This is of several kinds.

cumimpari, f. 116, with an odd, or terminal, leaflet,
as in Roses, and Elder, also Polemonium ceru-
leum, Engl. Bot. t. 14, and Hedysarum Onobry-
chis, t. 96.

cirrosum, f. 115, with a tendril, when furnished
with a tendril in place of the odd leaflet, as the
Pea and Vetch tribe; Piswm maritimum, t. 1046,

~Lathyrus palustris, t. 169, Vicia sativa, t. 334.
abrupte, f. 101, abruptly, without either a terminal
leaflet or a tendril, as Cassia Chamecrista, Curt.
Mag’, t. 107, and the genus Mimosa. See MW. pu-

136 COMPOUND LEAVES.

dica, the Common Sensitive-plant. This form
of leaf is much more uncommon than the impari-
pinnatum, and we have no perfect example of it
among British plants. The nearest approach to
itis the genus Oxgpbus, whose leaves have only
the rudiments of a tendril. .A truly wonderful
variety of the Orobus sylvaticus, Engl. Bot.
¢.518, with large simple leaves, has been found
in Wales. 3
- opposite, oppositely, when the leaflets are opposite,

or in pairs, as Saint-foin, ¢. 96, Roses, Siem an-
gustifolium, t. 139, &c.

alternatim, alternately, when they are alternate, as
Vicia dumetorum (Cracca sylvatica) Riv. Pent.
Trr. t.51, and occasionallyin our V’. sativa, lu-
tea, &c. .

interrupte, f. 107, interruptedly, when the principal

~. leaflets are ranged alternately with an interme-

diate series of smaller ones, as Spire@a Lilipen-
dula, Engl. Bot. t. 284, S. Ulmaria, t. 960, and
Potentilla anserina, t. 861.

articulate, jointedly, with apparent joints in the
common footstalk, as einmannia pinnata.

decurstve, decurrently, when the leaflets are decur-
rent, as Hryngium campestre, Engl. Bot. t. 57,
and Potentilla fruticosa, t. 88.

lyrato, f. 108, in a lyrate manner, having the ter-
minal leaflet largest, and the rest gradually smaller

as theyapproach the base, like Lrysimum precog,

7

COMPOUND LEAVES. 137

¢. 1129, and, with intermediate smaller leaflets,
Geum rivale, t. 106; also the Common Turnip.
Such leaves are usually denominated lyrate in
common with those properly so called (whose
shape is simple, and not formed of separate leaf-
lets); nor is this from inaccuracy in botanical
writers. |The reason is, that these two kinds of
leaves, however distinct in theory, are of ail
leaves most liable to run into each other, even on
the same plant, examples of which are frequent
in the class Zetradynamua.
verticillato, f. 109, in a whorled manner, the leaf-
lets cut into fine divaricated segments embracing
the footstalk, as Stumm verticillatum, Fl. Brit.
fingl. Bot. t. 395.
Auriculatum, f. 110, an auricled leaf, is furnished
at its base with a pair of leaflets, properly distinct,
but occasionally liable to be joined with it, as
Salvia triloba, #1. Grec.t.17, and Dipsacus pilo-
sus, Engl. Bot. t.877. . Linnzeus in the last ex-
ample uses the term appendiculatum, which 1s
correct, but superfluous, and I have therefore
ventured to apply it somewhat differently, p. 133.
Conjugatum, f. 105, conjugate, or yoked, consists
of only a pair of pinne or leaflets, and is much
the same as binatum. Instances of it are afforded
by the genus Zygophyllum, whose name, equiva-
lent to Yoke-leaf, expresses this very character ;
also Lathyrus sylvestris, Engl. Bot. t.805, and

138 COMPOUND LEAVES.

latifolius, t. 1108. Biyugwm, trijugum, quadri-
jugun, multijugum, &c. express particular num-
bers of pairs of leaflets, and are used for that
purpose where such discrimination is requisite for
specific characters, as in AZimose.

The different degrees in which leaves are com-
pounded are thus distinguished, without any re-
ference to the mode.

Compositum, f. 111, simply compound, as in the
above instances. |

Decompositum, f.112*, doubly compound, as Atha-
manta Libanotis, Lingl. Bot. t..138, A:gopodium
Podagraria, t. 940, and Fumaria claviculata,
Bi0S.

Supradecompositum, f. 113,.thrice comipound, or
more, as Caucalis Anthriscus, t. 987, C. dau-
coides, t. 197, and Bunium fleruosum, t. 988.
But

Bigeminatum, twice paired, as AZimosa Unguis cati,

_ Plum. Ic. t. 4.3 and tergeminatum, thrice paired,
as M. tergemina; also

Biternatum, f. 119, twice ternate, as gopodium,
Engl. Bot. t. 940; triternatum, thrice ternate,
as Mulmaria lutea, t. 588; and :

Bipinnatum, doubly pinnate, fripennatum, triply

_ pinnate, of which examples have just been given :

* Tinneus, in Pail, Bot. 47, gives an erroneous definition of this

term, which does not accord with his own use of it. Professor Ma.-
tyn has rightly defined it.

COMPOUND LEAVES. 139

all apply to the mode, as rell as the degree, in
which leaves are compounded.

Pedatum, f. 114, pedate, is a peculiar kind of leaf,
being ternate, with its lateral leaflets compounded
in their fore part, as /Zelleborus fetidus, Engl.
Bot. ¢t. 613, and H. niger, Curt. Mag. t. 8.
There is an affinity between a pedate leaf and
those simple ones which are three-ribbed at the
base, p. 128. See also the disposition of the
lateral veins in Aristolochia Clematitis, Engl.
Bot: t. 398.

In compounding the foregoing terms we must take
care not to express a contradiction. ‘Thus the leaves
of many MJimose, as the purpurea, Andr. Repos.
t. 372, and sensitiva, are conjugata pinnata, conju-
gate in the first instance, pinnate in the next, not con-
jugato-pinnata, of an intermediate nature between
conjugate and pinnate, which is impossible. Neither
are the leaves of A/imosa pudica digitato-pinnata,
for there is no medium between the two terms; but
they are digitate, or composed of leaflets proceeding
from the top of a common foot-stalk, and those leaflets
are pinnate. On the other hand ovato-lanccolaium,
lanceolate approaching to ovate, or edliptico-lanceola-
tum, approaching to elliptic, as in the Privet, Engl.
Bot. t. 764, whose leaves.often assume that shape,
are easily understood.

140

CHAPTER XVI.

——=

OF THE FUNCTIONS OF LEAVES.

Tue knowledge of the functions of leaves, and their
real use with regard to the plant, is a curious branch
of vegetable physiology, which made but a slow pro-
gress long after the nature of many other parts had
been deeply scrutinized and thoroughly explained.

Cesalpinus (De Plantis, p. 6.) thought leaves
merely a clothing, or a protection against cold and
‘heat. He conceived that the rays of the sun, being
moderated in passing through them, were prevented
from acting too violently on the fruit and young buds.
“ Accordingly,” says he, ‘‘ many. trees lose their leaves
in autumn, when their fruits are perfected, and their
buds hardened, while such as retain the fruit long,
keep also their leaves; even till a new crop -is pro-
duced, and longer, as in the Fir, the drbutus, and the
Bay. It is reported that in hot climates, where there
is almost perpetually a burning sun, scarcely any trees _
lose their leaves, because they require them for shade.”
Ceesalpinus goes on to show that leaves proceed from
the bark, with some remarks on the pith, (in which
we may trace the origin of the Linnean hypothesis of
vegetation,) but which are now superseded by more
accurate inquiries.

PERSPIRATION OF LEAVES. ]41

The above is certainly a very small part of the use
of leaves. Yet the observations of this writer, the
father of botanical philosophy among the moderns, are
so far correct, that if the leaves of a tree be stripped
off, the fruit comes to nothing, which is exemplified
every year in Gooseberry bushes devoured by cater-
pillars; and though the fruit-trees of warm climates,
partly naturalized with us, Grapes and Peaches for
instance, ripen their fruit sooner perhaps if partially
deprived of their leaves; yet if that practice be carried
too far, the fruit perishes, as gardeners who tried it
soon discovered. The White Mulberry indeed, culti-
vated in the south of Europe for the food of sikworms
only, bears wonderfully the loss of its foliage three or
four times a year. How far the fruit is injured nobody
thinks it worth while to inquire, as it is never eaten,
but it certainly does not fall off prematurely.

That Leaves imbibe and give out moisture has been
long known, this being one of the most obvious facts
belonging to them. Dr. Hales thought they might
probably imbibe air; but since his time, mere certain |
discoveries have been made concerning this point, as
well as the effects of light upon leaves, which also did
not escape the consideration of that great philosopher.
A}l these subjects we shall mention in their turn.

That Leaves give out moisture, or are organs of in-
sensible perspiration, is. proved by the simple experi-
inent of gathering the leafy branch of a tree, and im-
mediately stopping the wound at its base with mastick,

142 PERSPIRATION OF LEAVES,

wax, orany other fit substance, to prevent the effusion
of moisture in that direction. Ina very short time the
leaves droop, wither and are dried up. If the same
branch, partly faded, though not dead, be placed in a
very damp cellar, or immersed in water, the leaves
revive, by which their power of absorption is also
proved. Hence the use of a tin box to travelling bo-
tanists, for the purpose of restraining the evaporation
of plants, and so preserving them fresh for some days
till they can be examined, as well as of reviving faded
plants, if the inside of the box be moistened before
they are shut up in it.

Dr. Hales found that a plant of the Great Annual
Sunflower, Helianthus annuus, lost 1 1b. 14 oz. weight
in the course of twelve hours ina hot dry day. Ina
dry night it lost about 3 oz. ; in a moist night scarcely
any alteration was observable, but in a rainy night it
gained 2 or three oz. The surface of the plant compared
with that of its roots was, as nearly as could be calcu-
lated, in the proportion of five to two; therefore the
roots must have imbibed moisture from the earth of
the pot in which the plant orew, and which was all ©
previously weighed, in the same proportion of five to
two, otherwise the leaves would have faded. The same
experiment was made on the Vine, the Cabbage, &c.,
with various results as to the exact degree of perspira-
_ tion, but all proving it to be considerable. Evergreens
are found to perspire much less than other shrubs.

The state of the atmosphere has a great effect on the

SENSIBLE PERSPIRATION. 145

rapidity of this perspiration. Practical botanists know
how much sooner plants fade, and haymakers expe-
rience how much faster their work is done, some days
than others, and those days are by no means always
the most sunny. Ina hot dry day plants are often
exhausted, so as to droop very much towards evening,
especially in the dry unsheltered bed of a garden. Such
as have fleshy roots, indeed, have a singular power of
resisting drought, which has already been explained,
p. 87. Succulent plants, destined to inhabit sunny
rocks, or sandy deserts, imbibe with the greatest faci-
lity, and perspire very sparingly. Evergreens are not
generally very succulent, but their cuticle appears to be
constructed like that of succulent plants, so as to allow
of little evaporation. ‘The Cornelian Cherry, whose
immense perspiration we have recorded, p. 52, has a
thin dry leaf, capable of holding very little moisture.

The nature of the liquor perspired has been already
noticed, p. 52. In hot weather it has been observed
by Hales, Du Hamel and Guettard, to partake occa-
sionally of the peculiar scent of the plant that yields
it; but in general the odorous matter is of too oily a
nature to be combined with it.

The sensible perspiration of plants is of various
kinds. When watery, it can be considered only as a
condensation of their insensible evaporation, perhaps
from some sudden change in the atmosphere. Groves
of Poplar or Willow exhibit this phenomenon, even
in England, in hot calm weather, when drops ot clear

144, SENSIBLE PERSPIRATION.

water trickle from their leaves like a slight shower of
rain. Sometimes it is of a saccharine nature, as Dela
iiire observed in Orange trees; Du Hamel Arb. v. 1.
150. Itis more glutinous in the Zia or Lime-tree,
more resinous in Poplars, as well as in Cistus creticus,
from which last the resin called Labdanum is collected,
by beating the shrub with leather thongs. See Tour-
nefort’s Voyage, 29. In the Fraxinella, Dictamnus
dibus, it is a highly inflammable vapour. Ovid has
made an elegant use of the resinous exudation of
Lombardy Poplars, Populus dilatata, Ait. Hort. Kew.
v. 3. 406, which he supposes to be the tears of
Phaeton’s sisters, who were transformed into those
trees. Such exudations must be considered as effu-
sions of the peculiar secretions; for-it has been’ ob-
served that Manna may be scraped from the leaves of
Fravinus Ornus, Fl. Grec. t: 4, as well as procured

by incision from its stem. They are often perhaps a |

sign of unhealthiness in the pliant; at least such ap-
pears to be the nature of one kind of honey-dew, to
which the Beech in particular is subject, and which, in
conseyuence of an unfavourable wind, covers its leaves
~in the form of a sweet exudation, similar in flavour to
the liquor obtained from its trunk. So likewise the
Hop, according to Linnzus, Faun. Suec. 305, is af-
fected with the honey-dew, and its flowers rendered
‘abortive, in consequence of the attacks of the cater-
pillar of the Ghost Moth, Phalena Humuli, upon its
roots. In such case the saccharine exudation must

4

ABSORPTION OF LEAVES. 1435

decidedly be of a morbid nature*. That wax is also
an exudation from the leaves of plants, appears from
the experiments recorded by Dr. Thomson in his Che-
mistry, 0.4. 298, and it has been long ago asserted
that wax may easily be gathered from the leaves of
Rosemary. On this subject I have not made any ex-
periments to satisfy myself.

_ With respect to the absorbing power of leaves, the
best observations that have been made are those of
Bonnet, recorded in the beginning of his Recherches
sur ? Usage des Feuilles. His aim was, by laying leaves
of various plants upon the top of a jar of water, some
with their upper, and others of the same species with
their under, surfaces applied to the water, to discover
in which situation the leaves of each plant continued
longest in health and vigour, and also how far diffe-
rent species differed from each other in this respect.
The results were in many instances highly curious.

Of fourteen herbaceous plants tried by this philoso-
pher, six lived nearly as long with one surface applied
to the water as with the other; these were the com-
mon Arum maculatum, the French Bean, the Sun-
flower, Cabbage, Spinach, and the Small Mallow. By
the last I presume is meant Malva rotundifolia, Engl.
Bot. t. 1092. Six others, Plantain, White Mullein,

- * I do not mean to dispute the accuracy of Mr. Curtis’s excellent
paper, Tr. of Linn. Soc. 0. 6, written to prove honey-dew to be the
dung of Aphides. I only contend that there are more than one kind of
honey-dew.

L

146 ABSORPTION OF LEAVES.

the Great Mallow (probably MM. sylvestris, t. 671),
the Nettle, Cock’s-comb, and Purple-leaved Amaranth
(probably Amaranthus hypochondriacus), lived longest
with their upper surface laid upon the water. The
Nettle lived but three weeks with its under surface on
the water, and about two months in a contrary position.
The Mullein scarcely survived five or six days, and the
Amaranth not a week, in the first-mentioned posture,
while the leaves of the former remained in vigour about
five weeks, and of the latter three months, when their
upper surfaces imbibed the water. Marvel of Peru
and Balm, the two remaining plants of the fourteen on
which the experiment was made, had also an evident
advantage in receiving that fluid by their upper surfaces.
The leaves of some of the above species were found to
thrive better when their stalks only were immersed in
water, than when either of their sides was supplied with
it, and the reverse was observable in several others ;
but the White Mullein, the Plantain and the Amaranth
survived longer when they received the water by their
stalk than by their under surface, though not so long
as when it was applied to their upper sides.
Of sixteen trees tried by Bonnet, the Lilac and the
Aspen, Populus tremula, were the only leaves that
seemed to imbibe water equally well by either surface,
whilst all the others evidently succeeded best with their
under sides laid upon the water, being in that respect
the reverse of herbaceous plants. Of these the W hite
Mulberry leaf was the most remarkable, not living

ABSORPTION OF LEAVES. 147

more than five days when supplied by the upper sur-
face, while such as floated on their backs continued
in perfection near six months. The Vine, the Poplar,
(probably Populus nigra), and the Walnut, were no
less remarkable, for fading almost as soon, when fed
by their upper surface, as when left without any water
at all. Many of the other trees imbibed water as well,
or better, by their footstalks than by their upper sur-
faces. Hazel-nut and Rose leaves, when laid with
their backs upon the water, imbibe sufficiently to nou-
rish other leaves on the same branch; so will one
leaflet of a French bean supply its neighbour that does
not touch the water.

Those who wish to repeat these experiments should
be careful to choose full-grown healthy leaves, all as
nearly as possible of the same age and vigour. It is
also desirable that the precise species of plant should
be recorded by its scientific name. For want of this,
Bonnet, who despised method and nomenclature, has
left us in uncertainty concerning several of the plants
he examined. We ought to have been accurately in-
formed what species of Poplar differed so remarkably
in its power of absorption from the Aspen, another of
the same genus. We ought likewise to have been told
what Sun-flower, what Nettle, Amaranth and Mallows
were examined ; for want of which information the
authority of such experiments is much impaired.

From the foregoing observations we learn the im-
portance of shading and watering plants newly re-
L&

148 SARRACENIA,

moved, cuttings, grafts, &c. and on the other hand the
benefit of heat and air to promote due perspiration
and evaporation.

The perspiration of aquatic plants seems to be re-
markably copious, Of these some grow.constantly im-
mersed in the water, as most species of Potamogeton,
Pond-weed, Engl. Bot. t. 168, 297, 376, &c. Their
leaves are peculiarly vascular, and dry very quickly in
the air, withering in a very few minutes after exposure
to it. Their absorbing power seems equally great, so
that they appear to be continually, in their natural
situation, imbibing and giving out a quantity of water
much greater than has been observed in land plants.
Other aquatics, like the Nymphea, Engl. Bot. t. 160,
float with only the upper surface of their leaves ex-
posed to the air, which surface is so contrived that
water will scarcely remain upon it. These leaves,
though extremely juicy, dry with great rapidity, as
does every part of the plant when gathered. It is
probable that they imbibe copiously by their under
sides, and perspire by the upper.

The ceconomy of the Sarracenia, an American ge-
nus of which we now know four species, and of the
East Indian Nepenthes distillatoria, deserves particu-
lar mention. Both grow in bogs, though not absolute-
ly in the water. The former genus has tubular leaves
which catch the rain like a funnel and retain it; at
least such is the nature of S. purpurea, Curt. Mag.
,. 849, whose margin seems dilated expressly for this

SARRACENIA. 149

purpose, while the orifice of the tubular part just
below is contracted to restrain evaporation. Linnzeus
conceived this plant to be allied in constitution to.
Nymphea, and consequently to require a more than
ordinary supply of water, which its leaves were calcu-
lated to catch and to retain, so as to enable it to live
without being immersed in a river or pond. But the
consideration of some other species renders this hypo-
thesis very doubtful. S. flava, t. 780, and more espe-
cially S. adunca, Evot. Bot. t. 53, are so constructed
that rain is nearly excluded from the hollow of their
leaves, and yet that part contains water, which seems
to be secreted by the base of each leaf. What then is
the purpose of this unusdal contrivance? An observa-
tion communicated to me in 1805, in the botanic
garden at Liverpool, seems to unravel the mystery.
An insect of the Spher or Ichneumon kind, as far as 1
could learn from description, was seen by one of the
gardeners to drag several large flies to the Sarracenia
~ adunca, and, with some difficulty forcing them under
the lid or cover of its leaf, to deposit them in the tu-
bular part, which was half filled with water. All the
leaves, on being examined, were found crammed with
dead or drowning flies. The S. purpurea is usually
observed to be stored with putrefying insects, whose

scent is perceptible as we pass the plant in a garden; —
for the margin of its leaves is beset with inverted hairs,
which, like the wires of a mouse-trap, render it very
difficult for any unfortunate fly, that has fallen into

150 NEPENTHES.

the watery tube, to crawl out again. Probably the air
evolved by these dead flies may be beneficial to vege-
tation, and, as far as the plant is concerned, its curious
construction may be designed to entrap them, while
the water is provided to tempt as well as to retain
them. The Spher or Ichneumon, an insect of prey,
stores them up unquestionably for the food of itself or
its progeny, probably depositing its eggs in their car-
cases, as others of the same tribe lay their eggs in
various caterpillars, which they sometimes bury after-
wards in the ground. Thus a double purpose is an-
swered ; nor is it the least curious circumstance of the
whole, that an European insect should find out an
American plant in a hot-house, in order to fulfil that
purpose. | “

If the above explanation of the Sarracenia be ad-
mitted, that of the Nepenthes will not be difficult.
Each leaf of this plant terminates in a sort of close-
shut tube, like a tankard, holding an ounce or two of
water, certainly secreted through the foctstalk of the
leaf, whose spiral-coated vessels are uncommonly large
and numerous. The lid of this tube either opens spon-
taneously, or is easily lifted up by insects and small
worms, who are supposed to resort to these leaves in
search of a purer beverage than the surrounding swamps
afford. Rumphius, who has described and figured the
plant, says ‘ various little worms and insects crawl into
the orifice, and die in the tube, except a certain small
Squilla or shrimp, with a protuberant back, sometimes

AIR-VESSELS. OF THE LEAVES. 151

met with, which lives there.”"—I have no doubt that
this shrimp feeds on the other insects and worms, and
that the same purposes are answered in this instance as
in the Sarracenie. Probably the leaves of Dionea
muscipulay as well as of the Drosere, Engl. Bot.
t. 867—869, catch insects for a similar reason.

I proceed to consider the effects of Air and Light
upon vegetables.

Dr. Grew, by the assistance of the microscope, de-
tected a quantity of vesicles full of air in the leaves of
plants, as also the spiral-coated vessels of their stems,
which last he and all other physiologists, till very lately,
considered as air-vessels likewise. Malpighi made the
same observations about the same time; and as these
two acute and laborious philosophers pursued their in-
quiries without any mutual communication, their dis-
coveries strengthen and confirm each other. ‘Their
books have long served as magazines of facts for less
original writers to work with. From their remarks
physiologists have theoretically supposed that leaves
imbibed air, which the spiral vessels were believed to
convey all through the plant, in order that it might
act on the sap as it does on the animal blood. The
analogy thus understood was not correct, because air
is conveyed no further than the lungs of animals : but
without this hypothesis no use could be found for the
supposed longitudinal air-vessels.

The observations of Dr. Hales come next in order
‘to those of Grew and Malpighi. By means of the air-

152 AIR-VESSELS OF THE LEAVES.

pump, an instrument much in use in his time, Hales

obtained abundance of air from every part of the ve-
getable body, as well as from recently extracted sap.
Plants were found to perish very soon in an exhausted
receiver. Some of this great man’s experiments, how-
ever, require to be-received with caution. He rightly
remarked that air was not only taken in by plants very
copiously along with their food, but also imbibed by
their bark; see Veg. Staticks, chap. 5. But when,
from observing that it would freely from the bark per-
vade the longitudinal vessels of a branch, he concluded
that Malpighi and Grew were right in their ideas of
longitudinal air-vessels, he was inisled by appearances.
We cannot but be aware that, when a branch is
cathered, the sap must soon flow out of those spiral
coated tubes, which are large, elastic, and, no doubt,
irritable. After they are emptied, air may unquestion-
ably pass through them, especially when the whole
weight of the atmosphere is acting, as in Dr. Hales’s
experiments with the air-pump, upon so delicate a
fabric as the internal vascular structure of a plant,
forcing its way through pores or membranes not na-
turally designed to admit it. We must also recollect
that a plant, cut even for a short time, begins to lose
its vital principle, after which no just judgement can
be formed, by any experiments, concerning the move-

ments of its fluids in life and vigour. See Chapter 1.

These experiments of Dr. Hales therefore prove no
more than that the vegetable body is pervious in various

]

. »

EFFECTS OF AIR ON LEAVES. 1453

directions; and perhaps the only point they correctly
establish is, that air is imbibed through the bark, a
part known to be full of air-vessels. But the seventh
chapter of the Vegetable Staticks contains some re-
marks much more to our purpose. Dr. Hales there
clearly anticipates by conjecture, what succeeding phi-
losophers, more enlightened chemists, have ascer ee)
His words are remarkable :

““We may therefore reasonably conclude, that one
great use of leaves is what has been long suspected by
many, viz. to perform in some measure the same office
for the support of the vegetable life, that the lungs of
animals do, for the support of the animal life ; plants
very probably drawing through their leaves some part
of their nourishment from the air.” p. 326. A little
further on he adds, ‘‘ And may not light also, by freely
entering the expanded surfaces of leaves and flowers,
contribute much to the ennobling the principles of
vegetables r” p. 328.

Next in order of time to those of Hales follow the
experiments of Bonnet. We have already detailed his
observations on the power of leaves to imbibe moisture;
whence it is ascertained that plants are furnished with
a system of cuticular absorbents, which carry fluids
into their sap-vessels, so as to enable them in some
degree to dispense with supplies from the root. With
respect to the effects of air upon leaves, this ingenious
philosopher has not been equally successful. He is re-
corded as the discoverer of the expiration of plants; but

154 PURIFICATION OF AIR

it appears from his work that he merely observed the
bubbles of air which cling to. leaves, dead as well as
living, and mdeed to any other body, when immersed
in water and exposed to the light of the sun. He
found these bubbles disappeared in the evening, and
returned again when the sun shone, and he faithfully
reports that by their attachment to the surfaces of
leaves, the latter were rendered more buoyant, and
rose in the water ; a sure proof that the air had not
previously existed, in the same volume at least, in the
substance of those leaves. Accordingly, Bonnet con-
cluded that the latter, in imbibing the surrounding
water, left the air which had been contained in the
water, and that this liberated air became visible from
being warmed and rarefied by the sun. ‘This was as
near the truth as Bonnet could come, it not being then
known that light has a power of separating air of a
peculiar kind, carbonic acid gas, from water. I tind
no indications in his work of his having had any idea
of leaves absorbing air and giving it. out again; still
less of their effecting any change in its properties.
Dr. Priestley was the first who suggested this last-
mentioned quality in vegetables. He ascertained their

power of absorbing carbonic acid gas, denominated by ©

him fixed air, and giving out oxygen gas, or pure re-
spirable air. It was also his opinion that leaves imbibed
the former by their upper, and gave out the latter by
their under surface. He found some aquatic or marsh
plants extremely powerful in this respect, especially

a

BY LEAVES. 155

the Willow-herb, or Epilobium, and the Conferva, a
minute branching cotton-like vegetable which grows
in putrid water, and the production of which, in water
become foul from long keeping on ship-board, Dr.
Priestley judged to operate principally in TANF RS that
fluid to a state fit for use.

Dr. Ingenhousz, pursuing Dr. Priestley’s inquiries,
found light to be necessary to these functions, and
that, in the dark, leaves gave out a bad air. He ob-
served moreover that fruits and flowers almost invari-
ably gave out a bad, or carbonic, air, but more espe-
cially in the dark. He probably carries his ideas, of the
deleterious effects of this air on animal life, too far; for
no mischief has ever happened, as far as common ex-
perience goes, to persons sleeping in apple or olive
chambers, neither do the inhabitants of the confined
huts in Covent-garden market apparently suffer, from
living day and night among heaps of drying herbs.
Mischiefs have unquestionably arisen from flowers in a
bed-room, or any other confined apartment, but that
zs to be attributed to their perfumed effluvia. So the
bad effects, observed by Jacquin, of Lobelia longiflora
on the air of a hot-house, the danger incurred by those —
who sleep under the Manchineel-tree, Hippomane
Mancinella, or, as it is commonly believed, under a
Walnut-tree, are probably to be attributed as much to
poisonous secretions as to the air those plants evolve.

Dr. Ingenhousz introduced leaves into glass jars
filled with water, which he inverted in a tub of the

156 PURIFICATION OF AIR BY LEAVES.

same water, and placed the whole together in the sun-
shine. ois their under sides came streams or bubbles
of air, which collected in the inverted bottom of each
jar. The air thus procured proved oxygen gas, more
or less pure. The Nymphea alba, Engl. Bot. t. 160,
affords an extraordinary abundance of it. Dr. Ingen-
housz observed plants to be very various in their mode
of emitting these bubbles, but it was always uniform
in the same species. Air collected from water placed
in similar circumstances without plants, proved not
oxygen, but much worse than common air, viz. car-
bonic acid gas, which following chemists have con-
firmed, and which we have already mentioned. Ingen-
housz also found the air collected from plants under
water in the dark worse than common air, especially
that from walnut-leaves; which confirms the common
opinion, above alluded to, respecting this tree.

Plants purify air very quickly. A vine-leaf in an
ounce phial of carbonic acid gas, that immediately ex-
tinguished a candle, placed in the sun, without water,
changed it to pure respirable air in an hour and half.
Dr. Priestley found plants to alter even unmixed in-
flammable air, or hydrogen, especially the Epilobium
hirsutum, if Tmistakenot, and Polygonum Hydropiper.

Succulent plants are found to afford most air, in
consequence of the abundance of their Cellular Inte-
gument, or Parenchyma, in which, as I have hinted
in the fourth chapter, the chemical operations of he
leaves are performed. 9

TURNING OF LEAVES TO THE LIGHT. 157

That Light has a very powerful effect upon plants
has long been known, independent of the remarks. of
Hales or Ingenhousz. The green colour of the leaves
is owing to it, insomuch that plants raised in darkness

are of a sickly white. It has even been observed that

when light is admitted to the leaves through different
glasses, each tinged of a different prismatic colour, the
plant is paler in proportion as the glass approaches
nearer to violet. Tie common practice of blanching
Celery in gardens, by covering it up from the light, is
an experiment under the eyes of every one. ‘This
blanching of plants is called by the French étiolation,
and our chemists have adopted the term, though I
think they err in deriving it from étoile, a star. When
blanched plants are brought into the light, they soon
acquire their natural green colour, and even in the
dark theyare green, if exposed to the action of hy-
drogen gas. Tulip and Crocus flowers have long ago
been observed by Sennebier to be coloured even in the
dark, apparently because their colour depends on a
different principle from the green of leaves.

Light acts beneficially upon the upper surface of
leaves, and hurtiully upon the under side; hence the
former is always turned towards the light, in whatever
situation the plant may happen to be placed. ‘Trees
nailed against a north wall turn their leaves from the
wall, though it be towards the north, and in direct
opposition to those on a southern wall over agai

158 TURNING OF LEAVES TO THE LIGHT.

them. Plants in a hot-house all present the fronts of
their leaves, and this influences even the posture of the
branches, to the side where there is most light, but
neither to the quarter where most air is admitted, nor
to the flue in search of heat. If the branches of a
trained fruit-tree in full leaf be disturbed in their posi-
tion, the leaves resume their original direction in the
course of a day or two. The brighter the day, the
more quickly is this accomplished. If the experiment
be often repeated, they continue to turn, but more
weakly, and are mych injured by the exertion. Black
spots appear about the veins on their under sides, and
the cuticle scales off. Succulent leaves, though so
thick and firm as many of them are, have been ob-
served to be peculiarly sensible to light, while other
plants, as Mallows, according to Bonnet, are much
less so. The Miseltoe, Viscum album, Engl. Bot.
¢. 1470, the two sides of whose leaves are alike in ap-
pearance, and both equally, in general, presented to
the light, are not found to turn upon any change in
the posture of the branch. Neither do upright sword-

shaped leaves alter their position, because in them both >

sides must be presumed to perform the same functions
with respect to light as well as air.

Mr. Calandrini found vine-leaves turned to the light
when separated from the stem and suspended by a
thread. Of this any one may be easily satisfied, pro-
vided the experiment be made with sufficient care and

wl

TURNING OF FLOWERS TO THE LIGHT. 159

delicacy. Itisimportant, as demonstrating the turning
to be accomplished by an impression made on the
leaf itself, and not upon its footstalk.

Nor is this effect of light peculiar to leaves alone.
Many flowers are equally sensible to it, especially the
compound radiated ones, as the Daisy, Sun-flower,
Marigold, &c. In their forms Nature seems to have
delighted to imitate the radiant luminary to which they
are apparently dedicated, and in the absence of whose
beams many of them do not expand their blossoms
at all. The stately Annual Sun-flower, Helianthus
annuus, displays this phenomenon more conspicuously
on account of its size, but many of the tribe have
greater sensibility to light. Its stem is compressed in
some degree, to facilitate the movement of the flower,
which, after following the sun all day, returns after
sun-set to the east, by its natural elasticity, to meet his
beams in the morning. Dr. Hales thought the heat of
the sun, by contracting the stem on one side, occa-
sioned the flower to incline that way; but if so, it
would scarcely return completely at night. ‘There
can be no doubt, from the observation of other similar
flowers, that the impression is made on their radiated
florets, which act as wings, and seem contrived chiefly
for that purpose, being frequently destitute of any
other use. A great number of leaves likewise follow
the sun in its course; a clover-field 1s a familiar in-
stance of this. |

Of all leaves those of pinnated leguminous plants

160 SLEEP OF PLANTS.

are found most affected by light, insomuch that it
appears, in several cases, the sole cause of their expan-
sion, for when it is withdrawn they fold over each
other, or droop, as if dying; and this is called by
Linnzus the Sleep of Plants, who has a dissertation on
the subject in his Amenitates Academice. The term
Sleep may not really be so hyperbolical as at first sight
it seems; for the cessation of the stimulus of light, and
of the consequent restrained position of the leaves, may
be useful to the vegetable constitution, as real sleep is
to the animal. Another purpose is answered by the
nocturnal folding of some leaves, that they shelter their
flowers from the dew, the advantage of which we shall
explain hereafter.

Some pinnated leaves display a more extraordinary

sensibility, not merely to light, but to the touch of any —

extraneous body, or to any sudden concussion, as those
of Mimosa sensitiva, and pudica, Ovalis sensitiva,
and Smithia sensitiva, Ait. Hort. Kew. v. 3. t. 13.
An impression made even in the most gentle manner,
- upon one of their leaflets, is communicated in succes-
sion to all of them, evincing an exquisite irritability,
for it is in vain to attempt any mechanical solution of
this- phenomenon. One of this tribe, Hedysarum
gyrans, has a spontaneous motion in its leaves, inde-

pendent of any external stimulus, even of light, and —

only requiring a very warm still atmosphere to be per- _
formed in perfection, Each leaf is ternate, and the —

small lateral leaflets are frequently moying up and

ACTION OF LEAVES ON THE ATMOSPHERE. 161

down, either equably or by jerks, without any unifor-
mity or cooperation among themselves. It is difficult
to guess at the purpose which this singular action is
designed to answer to the plant itself; its effect on a
rational beholder cannot be indifferent.

The chemical actions of light, heat, and the compo-
nent parts of the atmospheric air, upon leaves, and,
where the latter are wanting, on the green stems of
plants, are now, as far as concerns all plants in com-
mon, tolerabty well understood. The observations and
experiments of Priestley and Ingenhousz have been
confirmed, extended in a variety of ways, or explamed
on the principles of improved chemistry, by Dr. Per--
cival and Mr. Henry in England, Dr. Woodhouse in
America, and M. Sennebier and M. Théodore de-
Saussure, as well as various other philosophers, on thé
continent of Europe. It is agreed that in the day-time
plants imbibe from the atmosphere carbonic acid gas,
(which was formerly called fixed air, and is an union
of oxygen and carbon,) that they decompose it, absorb
the carbon as matter of nourishment which is added
to the sap, and emit the oxygen. So they absorb the
same gas from water, when it is separated from that
fluid by the action of light. The burning of a candle,
or the breathing of animals, in confined air, produces
so much of this gas, that neither of these operations
can go on beyond a certain time ; but the air so con-
taminated serves as food for vegetables, whose leaves,
assisted by light, soon restore the oxygen, or, in other

M ai

162 CHEMICAL ACTION OF

words, purify the air again. This beautiful discovery,

for the main principles of which we are indebted to
the celebrated Dr. Priestley, shows a mutual depend-
ance of the animal and vegetable kingdoms on each
other, which had never been suspected before his time.

Comparative experiments upon the lower tribes of
these kingdoms have not yet been made, but they

would probably afford us a new test for distinguishing

them. The air so copiously purified by a Conferva,

one of the most inferior in the scale of plants, may be

very extensively useful to the innumerable tribes of
animated beings which inhabit the same waters. The_
abundant air-bubbles which have long ago given even

a botanical name to one supposed species, Conferva
bullosa, are probably a source of life and health to

whole nations of aquatic insects, worms and polypes,

whenever the sun shines.

In the dark, plants give out carbon and absorb
oxygen: but the proportion of the latter is small, com-
pared to what they exhale by day, as must likewise be
the proportion of carbon given out; else the quantity
of the latter added to their substance would be but
trifling, especially in these climates where the propor-
tion of day to night is nearly equal, and which, not-
withstanding, we know to be excessively luxuriant in
vegetation. Plants also give out azotic gas: but M. de —
Saussure is of opinion that this proceeds from their
internal substance ; and it appears by his experiments
to be rather a sign of disease or approaching decay,

- LEAVES ON THE ATMOSPHERE. 163

than a regular chemical production of their constitu-
tion when in health ; for Sennebier found the quantity
of oxygen emitted was in proportion to the thickness
of the leaf, or quantity of parenchyma. Yet the
parenchyma must be in its original organized state, for
when bruised its functions are destroyed.

Possibly such an alternation in the functions of vege-
tables between day and night may aflord a necessary
fepose to their vital principle, whose share in them
we know to be of primary importance. Whatever may
happen to plants in the dark, there can be no doubt
of their principal business in the ceconomy of nature
being what we have described. The most luminous
and compendious view of the whole subject is given
by Dr. Thomson of Edinburgh in the fourth vol. of
his Chemistry, which is well worth the attention of
those who wish to enter more aeeply into all the va-
rious chemical examinations respecting it than suits
our purpose. It is only necessary to add a short view
of Dr. Darwin's hypothesis which Dr. Thomson has
_not mentioned, probably on account of its insufficiency.
That lively writer thought the watery perspiration of
leaves, acted upon by light, gave out oxygen for the
use of the plant itself, such oxygen being immediately
absorbed by the air-vessels. This is by no means ade-
quate to explain any of the phenomena, but rather
contradictory to most of them, and is totally superseded
by the observations and experiments of other writers.

There can be no question of the general purpose

M 2

164 CHEMICAL ACTION OF

answered to the vegetable constitution by these func-
tions of leaves. They confirm Mr. Knight's theory of
vegetation, who has proved that very little alburnum
or new wood is secreted when light is kept from the
leaves. They also help us to understand how essen-
tial oils may be produced, which are known, as well as
sugar, to be composed of oxygen, hydrogen and car-
bon in different proportions. We can now have a ge-
neral idea how the nutritious sap, acted upon by all
the agents above mentioned during its stay in the cel-
lular substance of the leaf, and returned from thence
impregnated with them into the bark, may prove the
source of increase, and of peculiar secretions, in the
vegetable frame. That portion of sap sent to the flower
and fruit undergoes no less remarkable changes, for
purposes to which those curious organs are devoted ;
nor is it returned from thence, as from the leaves, to
‘answer any furtherend. The existence of those organs
is still more temporary, and more absolutely limited
to their own purposes, than even that of the leaves,
from whose secretions theirs are very distinct.

But when we attempt to consider how the particu-
lar secretions of different species and tribes of plants
are formed ; how the same soil, the same atmosphere,
should in a leaf of the vine or sorrel produce a whole- —
some acid, and in that of a spurge or manchineel a —
most virulent poison ; how sweet and nutritious her-
bage should grow among the acrid crowfoot and aco-
nite, we find ourselves totally unable to comprehend —

LEAVES ON THE ATMOSPHERE. 165

the existence of such wonderful powers in so small
and seemingly simple an organ as the leaf of a plant.
The agency of the vital principle alone can account
for these wonders, though it cannot, to our understand-
ing, explain them. “ The thickest veil,” says Dr.
Thomson at the end of his chapter on vegetation,
“covers the whole of these processes ; and so far have
philosophers hitherto been from removing this veil,
that they have not even been able to approach it. All
these operations, indeed, are evidently chemical de-
compositions and combinations ; but we neither know
what these decompositions and combinations are, nor
the instruments in which they take place, nor the
agents by which they are regulated.”

The vain Buffon caused his own statue to be in-
scribed ‘‘ a genius equal to the majesty of nature,”
but a blade of grass was sufficient to confound his

pretensions.

166

CHAPTER XVII.

Se
s

OF THE SEVERAL KINDS OF FULCRA, OR APPEN-
DAGES TO A PLANT.

Tue word Fulerwm, whose proper meaning is a prop
or support, has been applied by Linnzeus not only to
those organs of vegetables correctly so denominated,
such as tendrils, but also to various other appendages
to the herbage of a plant, none of which are universal,
or essential, nor is there any one plant furnished with
them all. I prefer the English term Appendages for
these organs in general, to Props, because the latter
applies only to one of them. Seven kinds of these
are distinguished by Linnzeus, nor do I tind it neces-
sary to enlarge that number.

1. Stipula. The Stipula, a leafy appendage to the
proper leaves or to their footstalks. Itiscommonly —
situated at the base of the latter, in pairs, and is
extremely different in shape in different plants.

The most natural and usual situation of the Sti- ~
pulas is in pairs, one stipula on each side of the base
of the footstalk, as in Lathyrus latifolius, Engl.
Bot. t. 1108, whose:stipulas are half arrow-shaped,
f.115; also in Willows, as Salix stipularis, t. 1214,
and S. aurita, t.1487. In Rosa, Potentilla, and

OF THE FULCRA. 167

many genera allied to them, the stipulas are united
laterally to the footstalk, f- 116. See Potentilla
alba, t. 1384. In all these cases they are extrafo-
liacee, external with respect to the leaf or foot-
stalk; in others they are intrafoliacea, internal, and
are then generally simple, as those of Polygonum,
t. 1389, 756, &c. Ina large natural order, called
Rubiacee, these interna! stipulas in some cases em-
brace the stem in an undivided tube above the inser-
tion of the footstalks, like those of Polygonzm just
mentioned ; in others, as the Coftee, Coffea arabica,
and the Hamellia patens, Exot. Bot. t. 24, they are
separate leaves between the footstalks, but meeting
just above their insertion. The European Rudbiacee:
have whorled leaves, as Asperula, Galium, Rubia;.
&e. ; but Asperula cynanchica, Engl. Bot. t.33, has
‘sometimes two of its four leaves so small as to look
like-stipulas, seeming to form an intermediate link
between such as have whorled leaves, and such as
have opposite ones with stipulas. The next step
from Asperula is Diodia, and then Spermacoce. In
the two last the bases of the stipulas and footstalks
are united into a common tube.

Some stipulas fall off almost as soon as the leaves
are expanded, which is the case with the Tulip-tree,
Liriodendron tulipifera; in general they last as long
as the leaves.

The absence or presence of these organs, though
generally an indication that plants belong to the -~

168 OF THE FULCRA,

same natural order and even genus, is not invariably
so. Some species of Cistus have stipulas, others
none, which is nearly the case with grasses. ‘The
stipula in this, one of the most distinct of all natural
orders, is peculiar, consisting of an internal white
membrane crowning the sheath of their leaf, and
clasping the culm. See Phalaris canariensis, Engl.
Bot. t. 1310, and Lagurus ovatus, t. 1334. In
Aria cerulea, t.750, a few ninute hairs supply its
place, while Sesleria c@rulea, t. 1613, and some
maritime grasses, have scarcely more than the rudi-
ment of astipula. Old writers call this organ in
grasses by a peculiar name liguda, and others deno-
minate it membrana foliorum, but both terms are
superfluous. A curious instance of stipulas supply-
ing the place of leaves is observable in Lathyrus
Aphaca, t. 1167, which has only one or two pair
of real leaves on the seedling plants, and those soon
disappear, serving chiefly to prove, if any proof were
wanted, that the rest are true stipulas. | :

Remarkably scariose, or dry membranous stipulas
are seen in I/lecebrum Paronychia, I'l. Grec.t. 246,
and in the genus Pinus. |

)

2. Bractea. The floral leaf, a leafy appendage to the
flower or its stalk. It is of a variety of forms, and
sometimes green, sometimes coloured. The Lime-
trees, Tilia europea, f.117, Engl. Bot. t.610,
and parvifolia, t. 1705, havea very peculiar oblong

OR APPENDAGES OF PLANTS. 169

pale floral leaf, attached to the flower-stalk. The
_ Lavenders, f. 118, see Curt. Mag. ¢t. 400 and 401,
have coloured bracteas, and the Purple-toppedClary,
Salvia Horminum, Il. Grec. t. 20, exhibits a gra-
dation from the proper leaves to green bracteas, and
from them to coloured ones, which last are barren,
or unaccompanied by flowers. Hence I am induced
to believe this plant a mere variety of S. viridis,
t. 19, all whose bracteas are green and fertile.
Bartsia alpina, Engl. Bot. t. 361, and Melam-
pyrum arvense, t. 53, display an elegant transition
from leaves to coloured bracteas. The Orchis tribe
have green leafy bracteas, different in size in diffe-
rént species. A most beautiful large and coloured
bractea is produced in Mussenda frondosa, Hort.
Mal. v. 2. t. 18, from one of the teeth of the calyx,
also in M. glabra of Willdenow, and two new
species brought from America by Mr. John Fraser.
Spinous bracteas of a curious construction guard the
calyx in Atractylis cancellata, f. 119. Linnwus ob-
serves that no bracteas are to be found in the class
Tetradynamia.

The ocrea of Rottboll, Willdenow’s Principles
of Botany, 50, which enfolds the flower-stalks in
Cyperus, see Engl. Bot. t. 1309, seems to me a
species of. bractea.

. Spina, f. 120. A Thorn. This proceeds from the
wood itself, and is either terminal like Huppophae

170 | OF THE FULCRA,

rhamnoides, Engl. Bot. t. 425, Rhamnus cathar-
ticus,t. 1629 ; or lateral as Cr atagus (or Mespilus)
Crus-galli, tomentosa, parvifolia, &

Linneeus observes that this sanaiere disappears
by culture, as in the Pear-tree, Pyrus sativa, which
when wild has strong thorns; hence he denominates
such cultivated plants tamed, or deprived of their
natural ferocity. Professor Willdenow, Principles
of Bot. t. 270, considers thorns as abortive buds,
and thence very ingeniously and satisfactorily ac-
counts for their disappearance whenever the tree re-
ceives more nourishment.

The permanent footstalks of the Gum Tragacanth
shrub, Astragalus Tragacantha, are hardened into
real spines, as are the flower-stalks in Pisonia, as
well as the stipulas of Xanthium spinosum and the
Mimose.—Linn. Mss. |

4. Aculeus, f. 121, a Prickle, arises from the bark
only, and comes off with it, having no connexion
with the wood, as in Rosa, Rubus (the Bramble
Raspberry, &c.), and i yphus, Willd. Sp. Pl.
v. 1. 1102.

This is not liable to disappear by culture, being
very distinct in nature from the last.

5. Cirrus, t. 9. f. 122. A Tendril. This is indeed
properly called a fulcrum or support, being intended
solely to sustain weak and climbing stems upon more

OR APPENDAGES OF PLANTS. 171

firm and sturdy ones. By its means such climbers
often reach, in tropical forests, to the summits of
lofty trees, which they crown with adventitious blos-
soms. Tendrils or claspers when young are usually
put forth in a straight direction; but they. presently
become spiral, making several circumvolutions, by
which they take hold of any thing in their way, and
then assume a firmer texture. After accomplishing
a certain number of turns in one direction, some
tendrils have a power of twining subsequently the
contrary way; many of them moreover are branched
or compound, so that the chances of their meeting
with a support are multiplied. The Vine, Vitis
vinifera, the various species of Passion-flower, and
the Pea or Vetch tribe afford gocd examples of
spiral tendrils. The Virginian Creeper Hedera, or,
as it ought to be called, Vitis, quinguefolia, has
branched tendrils, whose extremities adhere to the
smoothest flint, like the fibres of Ivy. Gloriosa
superba, f. 76, Andr. Repos. t. 129, and Flagel-
laria indica, have a simple spiral tendril at the end
of each leaf; for they belong to the Monocotyle-
dones, the structure of whose whole herbage is gene-
rally of the most simple and compendious kind.
The flower-stalks of Cardiospermum Halicacabum
bear tendrils; but a most singular kind of tendril,
_ if it may so be called, which certainly has a right to
the name of fulcrum, is found in the Annona hexa-
petala, Linn. Suppl. 270. The flower-stalk of this

172 _ OF THE FULCRA, .

tree forms a hook, and grasps the neighbouring
branch, serving to suspend the fruit, which is very
heavy, resembling a bunch of grapes, and indicates
the plant in question to be either a Michelia or an
Uvaria. |

. Glandula, a Gland, is defined by Linneus as a
little tumour discharging a fluid. Such are abun-
dant on the stalk and calyx of a Moss Rose, f. 123,
Curt. Mag. t. 69, and between the serratures of
the leaf of Salix pentandra, Bay-leaved Willow ;
also on the footstalks of Viburnum Opulus, Engl.
Bot. t. 332, and various species of Passion-flower.
The liquor discharged is in the first-mentioned in-
stances resinous and fragrant, in the latter a sort of
honey. te

. Pilus, f. 124. A Hair. This, according to the
Linnean definition, is an excretory duct of a bristle-
like form. Such it undoubtedly is in the Nettle,
Urtica, Engl. Bot. t. 148, and ¢. 1236, whose
bristles are tubular and pervious, having each a bag

of poison at its base, like the fang of a serpent; as:

well as in numerous plants whose hairy coats exude
a viscid moisture. But the hairs which clothe many
plants are merely a protection against cold, heat, or
insects. Sometimes they are hooked, sometimes
branched and entangled, as in Mullein, Verbascum,
t. 549, &c. In Croton, Solanum, and Lavatera,

—

OR APPENDAGES OF PLANTS. 173

they have often a starry figure. Very generally they
are found, under a microscope, to be curiously
jointed. Some Begonie bear on their leaves flat
little straps called by authors ramenta, shavings,
instead of cylindrical hairs; but I know not that
they at all differ in nature froin the usual pubescence,
nor do they merit to be particularly distinguished.
Some of the natural order of asperifolie, as Echium,
t. 181, and Lycopsis, t. 938, especially some exotic
species of this order, are clothed with curious white
hard tubercles from which their bristles proceed.
Echium pyrenacum, Desfont. Atlant. v. 1. 164, is
an instance of this, f. 125.

The pubescence of plants varies greatly in degree
according to differences of soil or exposure; several
kinds, as Adentha hirsuta, t. 447, 448, naturally
hairy, being occasionally found smooth, but if trans-
planted they soon resume their proper habit. Yet
the direction of the hairs or bristles proves a very
sure means of distinguishing species, especially in
the genus Mentha, the hairs about whose calyx and
flower-stalk point ditferently in different species, and
I have found itthe only infallible distinction between
one Mint and another. See Trans. of Linn. Soc.
v. 5.171. Theaccurate Dr. Roth has lately applied
the same test to the species of AZyosotis, which all
botanists before him had either confounded under
M. scorpioides, Engl. Bot. t. 480, or else separated
upon vague principles. Some species of Galium

174 OF THE FULCRA, ETC.

are admirably characterized by the bristles of their
leaves, or of parts of their leaves, being hooked
backward or forward. We therefore accept the
272d maxim of Linneus’s Philosophia Botanica
with that limitation which he himself has allowed in
his commentary upon it. ‘The Pubescence,” says
he, ‘is a ridiculous distinction, being for the most
part effaced by culture.” After quoting examples,
he concludes: “ We are therefore not to have re-
course to the hairiness or spines of plants but in case
of absolute necessity.” Such necessity every bota-
nist will allow to have existed in the AZenthe and
in Myosotis scorpioides; and though the degree of
pubescence varies from culture, and even its striuc-
ture be changeable, as in Hedypnois hispida, Engl.
Bot. t. 554, and hirta, t. 555, its direction is I
believe as little liable to exception as any character
that vegetables present.

175

CHAPTER XVIII.

OF THE INFLORESCENCE, OR MODE OF FLOWERING,
AND ITS VARIOUS FORMS.

Iyrrorescence, inflorescentia, is used by Linnzus
to express the particular manner in which flowers are
situated upon a plant, denominated by preceding writers
the modus florendi, or manner of flowering. Of this
the several kinds are distinguished as follows.

VERTICILLUS, f/. 126. A Whorl. In this the flowers
surround the stem in a sort of ring; though they
may not perhaps be inserted on all sides of it, but
merely on two opposite ones, as in Dead Nettle,
Lamium, Engl. Bot. t. 768—770, Mentha rubra,
t. 1413, and Clinopodium vulgare, t. 1401 ; or even
on one side only, as Rwmex maritimus, t. 725.
The flowers of Hippuris vulgaris, t. 763, are truly
inserted in a ring round the stem, f. 127; but they
are not whorled independent of the leaves, and are
therefore more properly, with a reference to the
leaves, denominated axillary and solitary.

Racemus, f. 128, a Cluster, or Raceme, consists
of numerous rather distant flowers, each on its own
proper stalk, and all connected by one common
stalk, as a bunch of Currants, Rides rubrum, Engl.

176 OF THE INFLORESCENCE.

Bot. t. 1289, nigrum, t. 1291, and Orobus sylva-
ticus, t. 518. A cluster is most generally drooping
or pendulous, and the flowers are all expanded
nearly at the same time. :

A compound racemus occurs in Solanum Dul-
camara, t. 565, and an aggregate one, several being
gathered together, in dctea racemosa, Dill. Elth.
¢. 67; but the example of a bunch of Grapes,
quoted by Linnzeus for a racemus, appears to me a
true thyrsus; see below.

Spica, f. 129, a Spike, bears numerous flowers
ranged along one common stalk, without any partial
stalks, as in Satyrium hircinum, Engl. Bot. t. 34,
Orchis bifolia, t. 22, Plantago major, t. 1558,
and media, t. 1559, Potamogeton heterophyllum,
¢. 1285, and fluitans, t. 1286; but this is so seldom
the case, that a little latitude is allowed. Veronica
spicata, t. 2, therefore, f. 130, and Ribes spicatum,
t. 1290, as well as the Common Lavender, Lavan-
dula Spica, are sufficiently good examples of a
spike, though none of them has entirely sessile
flowers; and Linnewus uses the term in numerous —
instances where it is still less correctly applicable.
A spike generally grows erect. Its mode of expan-
sion is much more progressive than that of the
raceme, so that a long period elapses between the
fading of the lowest flowers and the opening of the
upper ones. The flowers are commonly all crowded

OF THE INFLORESCENCE. 177

close together, or if otherwise, they form separate
groups, perhaps whorls, when the spike is said to
be either interrupted, or whorled; as in some Mints.
In Sanguisorba officinalis the spike begins flower-.
ing at the top. See Capitulum below.

A compound spike is seen in Lavandula pinnata,
Curt. Mag. t. 401, and LZ. abrotanoides of Willde-.
now.

_ Spica secunda, a spike whose ilowers lean all to.
one side, occurs in Nardus stricta, Engl. Bot. t.290.

Spicula, f. 131, a Spikelet, is applied exclusively
to grasses that have many florets in one calyx, such
florets, ranged on a little stalk, constituting the
spikelet, which is therefure a part of the flower it-
self, and not of the inflorescence; see Poa aqua-
tica, t. 1315, fluitans, t. 1520, Briza minor,
#1316, &e-

CorymBus, /. 132, a Corymb, is a spike whose par-
tial flower-stalks are gradually longer as they stand
Jower on the common stalk, so that all the flowers
are nearly on a level, of which Spirea opulifolia,
a common shrub in gardens, is an excellent speci-
men. The Linnean class Tetradynamia exemplifies
this less perfectly, as Cardamine pratensis, Engl.
Bot. t.776, Cheiranthus sinuatus, t.462, and the
common Cabbage, Brassica oleracea, t. 637, in
which the corymbus of flowers becomes a racemus
of fruit, as happens also in that section of the Ve-

N 3

178 OF THE INFLORESCENCE.

ronice, entitled by Linneeus corymboso-racemose.
The flowers of Yarrow, f. 133, Achillea, Engl.
Bot.t. 757 and 758, with several others of the com-
pound class, as well as the Mountain Ash, ¢. 337,
grow In a corymbose manner, though their inflores-
cence may not come exactly alas the above de-
finition. Itis worthy of remark that Linnzeus in
that definition uses the word spica, not racemus,
nor has he corrected it in his own copy of Phil. Bot.
_p.41, though he has properly. altered a slip of the
pen in the same line, petiolis, to pedunculis*. ‘This
_ shows he did not restrain his idea of a spike abso-
lutely to sessile flowers, but admitted that extended
signification which nature justifies. Many plants

acquire partial stalks as the fruit advances towards |

‘

maturity.

TFascrcuLus, f. 134, a Fascicle, is applied to flowers
on little stalks, variously inserted and subdivided,
collected into a close bundle, level at the top, as
the Sweet William, Dianthus barbatus, Curt. Mag.
¢. 207, and D. Armeria, Engl. Bot. t. 317.

CaAPITULUM, f. 135, a Head or Tuft, bears the flowers
sessile in-a globular form, as Statice Armeria,

* It might be expected from the numerous learned editors and
copiers of this and other works of Linnzus, that they should correct
such manifest errors as the vate which any tyro might perceive.

OF THE INFLORESCENCE. 179

t. 296, Adora Moschatellina, t. 453, and Gom-
phrena globosa, the Globe Amaranthus of the gar-
dens.

Perhaps the inflorescence of Sanguisorba offici-
nalis, t. 1312, might be esteemed a capitulum, be-
cause its upper flowers come first to perfection, as
in Adoxa, which seems contrary to the nature of
a spike; but it does not appear that all capitate
flowers expand in the same way, and Sanguisorba
canadensis has a real spike, flowering in the usual -
manner, from the bottom upwards. So Allium de-
scendens, Curt. Mag. t.251, opens its upper, or
central, flowers first, contrary to the usual order in
its genus ;_ both which instances prove such a diver-
sity to be of small moment. |

UMBELLA, an Umbel, for which some authors retain
the obsolete old-English name of Rundle. In this
several flower-stalks, or rays, hearly equal in length,
spread from one common centre, their summits
forming a level, convex, or even globose surface,
more rarely a concave one. When each ray is
simple and single-flowered, it is called a simple um-
bel, f- 136, as those of Allium ursinum, Engl. Bot.
t. 122, Ivy, ¢. 1267, Primula veris, t.-5, farinosa,
t.6, elatior, t. 513, and Eucalyptus resinifera,
Exot. Bot. t. 84. In a compound umbel each ray
or stalk mostly bears an wmbellula, or partial umbel,
as Athamanta Libanotis, Engl. Bot. t. 138. This

N 2

180 OF THE INFLORESCENCE.

is usually the case in the very natural order of plants
called umbelliferous, f- 138, to which the last-men-
tioned, as well as the common Carrot, Parsnep,
Parsley, Hemlock, &c. belongs.

A few only of this order have simple umbels, as
Hydrocotyle vulgaris, t. 751, and the curious
Astrantia, f. 187, and Kriocahe, Exot. Bot.
t. 70—79. In Euphorbia the umbel is differently
compounded, consisting of 3,4, 5 or numerous rays,
each of which is repeatedly subdivided, either in a
three-fold or forked manner. See Hngl. Bot. t. 883,
959, &c. |

Cyma, f. 139, a Cyme, has the general appearance _
of an umbel, and agrees with it so far that its com-
mon stalks all spring from one centre, but differs in
having those stalks variously and alternately sub-
divided. Examples are found in Viburnum, Engl.
Bot. t. 331, 332, and the common Laurustinus, as
also in Sambucus, Elder, t. 475,476. This mode
of inflorescence agrees with a corymbus also in ge-
neral aspect; but in the latter the primary stalks
have no common centre, though the partial ones
may sometimes be umbellate, which last case is pre-
cisely the reverse of a cyma.

PANICULA, f. 140, a Panicle, bears the flowers in
a sort of loose subdivided bunch-or cluster, without
any order. When the stalks are distant, it is called

~~

_ OF THE INFLORESCENCE. 181

diffusa, a lax or spreading panicle, as in Sarifraga
umbrosa, t. 663, so frequent im gardens under the
“name of London Pride, and S$. Geum, ¢. 1561, but
particularly in many grasses, as the common culti-
vated Oat, and Avena strigosa, t. 12663 in this
tribe the branches of the panicle are mostly semi-
-verticillate; see Aira aquatica, t. 1557. A divari-
cated panicle is still more spreading, like those of
Prenanthes muralis, t. 457, and Spergula arvensis,
. #. 1535; the last being dichotomous or forked. A
- dense or crowded panicle, coarctata, is observable
in Ailium lendigerum, t. 1107, and Agrostis stolo-
-nifera, t. 1539; but still more remarkably in Phlewi
paniculatum, t. 1077, whose inflorescence looks, at
first sight, like a cylindrical spike, but when bent to
either side, it separates into branched lobes, con-
stituting a real panicle.

Tuyrsus, f. 141, a Bunch, is a dense or close panicle,
more or less of an ovate figure, of which the Lilac,
“Syringa vulgaris, Curt. Mag. t. 183, Tussilago
hybrida and Petasites, Engl. Bot. t. 430, 431, are
examples cited by Linneus. I presume likewise to

“itis vinifera, as a

consider a bunch of grapes, /
true ¢hyrsus, to the characters and appearance of
which itcorrectly answers. Its ultimate terminations
are sometimes obscurely umbeilate, especially while

in blossom, which is no objection here, but can

182 OF THE INFLORESCENCE.

never be the case in a racemus, whether-simple or

compound. See Racemus.

Of simple flower-stalks, whether solitary or clustered,
radical or cauline, axillary, lateral or terminal, we have
already spoken. | ,

Linneus remarks that the most elegant sid cha-
racters are taken from the inflorescence. Thus the
Apple, Engl. Bot. t. 179, and the Pear, form two
species of Pyrus, so far at least a most natural genus,
the former of which bears an umbel, the latter acorymb.
Pyrola uniflora, t. 146, secunda, t. 517, and umbel-
lata, Curt. Mag. t.'778, are admirably distinguished
by their several forms of inflorescence.

183

CHAPTER XTX.

OF THE FLOWER AND FRUIT.

Havinc examined the general structure and external
form of plants, we now come to more important and.
even essential, though more transitory organs—the
flower and fruit, or parts of fructification. By these
each species is perpetually renewed without limits, so
far at least as the observation of mankind has reached;
while, as we have already mentioned, all other modes
of propagation are but the extension of an individual,
and sooner or later terminate in its total extinction.

| Nothing can be more happy than the Linnean de-
finition of these organs; Phil. Bot.52. ‘The fruc-
tification is a temporary part of vegetables, destined
for the reproduction of the species, terminating the old
individual and beginning the new.”

Pliny had long ago beautifully said that “ blossoms
are the joy of trees, in bearing which they assume a
new aspect, vyeing with each other in the luxuriance
and variety of their colours.” lLinnzus has justly
applied this to plants in general, and, improving upon
the idea, he considers their herbage as only a mask or
clothing, by no means indicative of their true nature
or character, which can be learned from the flower and
fruit alone. 3 |

184 OF THE PARTS

Mr. iXnight has traced his central vessels, by which
the sap is conveyed from the root, into the flower and
fruit. On the returning sap in the bark of these parts
he has not been able to make any distinct observation ;
but he has determined that no matter of increase is
furnished from the flowers or their stalks, as from

leaves, to the part of the branch below them, nor in-
deed to any other part, Phil. 7rans. for 1801, p. $40.
There can be no doubt that certain parts of the flower,
which we shall presently describe, perform functions
respecting air and light analogous to those of leaves,
but entirely subservient to the benefit of the flower and
fruit. Their secretions, formed from the returning sap, _
are confined to their own purposes. As soon as these
are accomplished, a decided separation of vessels takes
_ place, and the ripe fruit, accompanied perhaps by its
stalk, falls from the tree. Dr. Hales tried in vain to
give any flavour to fruit by the most penetrating and
volatile fluids conveyed through the sap-vessels; for
the laws of secretion are absolute in the organs of the
flower, and their various results are, if possible, more
strikingly distinct than even those we have contem-
plated in the leaves.

It is scarcely necessary to repeat that the fructifica-
tion is essential to vegetables. A plant may be destitute
of stem, leaves, or even roots, because, if one of these
parts be wanting, the.others may perform its functions,
but it can never be destitute of those organs by which
its species is propagated. Hence, though many indi-

OF FRUCTIFICATION. 185

vidual plants may be long without blossoms, there
are none, so far as nature has been thoroughly inves-
tigated, that are not capable, in favourable circum-
stances, of producing them, as well as seeds; to whose
perfection the blossoms themselves are altogether sub-
servient. | :

Linneus distinguishes seven parts of fructification,
some of which are essential to the very nature of a
flower or fruit, others not so indispensably necessary,
and therefore not universal.

I. Calyx, the Calyx or Flower-cup, generally resem-
bling the leaves in texture and colour, and forming
the outermost part of a flow er. This is not essential,
_and is often absent.

II. Corolla, the Corolla, or more delicate coloured
internal leaf or leaves, properly petals, of a flower,
likewise not essential.

III. Stamen, or Stamina, the Stamen or Stamens,
commonly of a slender or thread-like form, bearing
some kind of knob or cellular body, and ranged
internally with respect to the Corolla. These are
essential.

>

-

IV. Pistillum, or Pistilla, the Pistil, or Pistils, in the
centre of the flower, consisting of the rudiments of

186 DIFFERENT KINDS OF CALYX.

the fruit, with one or more organs attached to them,
and, of course, essential.

V. Pericarpium, the Seed-vessel, of a pulpy, woody,
or leathery texture, inclosing the seeds, but walking
in many plants.

VI. Semen, the Seed, the perfecting of which i is the
sole end of all the other parts.

VII. Receptaculum, the Receptacle, basis or point of
connection. This must necessarily be present in
some form or other.

I. Catyx. The flower-cup, or more correctly the
external covering of the flower, when present, was
originally divided by Linnzeus into seven kinds,
some of which are more justly so denominated than
the others, and I have ventured to make an altera-
tion in his list.

1. Perianthium, f. 142. Calyx, properly and com-
monly so called, when it is contiguous to and makes
a part of the flower, as the five green leaves which
encompass a Rose, including their.urn-shaped base;
the two green bristly ones which enfold the bud in
Glaucium luteum, Fl. Brit. Engl. Bot. t.°8; the
tubular part, comprehending the scales at its base,

OF THE INVOLUCRUM. 187

in the Pinks, ¢. 61, 62, or the globular scaly cup in
_ Centaurea, t. 56. The Tulip, ¢. 63, is a naked
flower, having no calyx at all.

This part is of an infinite variety of forms in
different genera, being either simple or compound,
divided or undivided, regular or irregular. In some
instances it is permanent till the fruit is ripe,in others
it falls even before the flower is well expanded.

Some genera have a double pertanthium, as
Malva, t. 671, or even a triple one, as Scabiosa,
€43 ki,

2. Involucrum, f.143. Involucre of Professor Martyn ;
but I generally retain the Latin termination. ‘This
is remote from the flower, and can scarcely be di-
stinguished clearly from a Bractea. The term was
first adopted by Linneus, at the suggestion of his
friend Artedi, in order to distinguish the genera of
umbelliferous plants, for which purpose the latter
deemed the part in question very important. But

_ according to the laws which Linneus had laid
down, the parts of the flower and fruit alone were to
afford generic characters, and the most sound bota-
nists have ever since kept to this rule, with infinite
advantage over less correct ones, however ready to
derive ideas respecting the natural habit, and secon-
dary characters, of a genus, not only from the in-
florescence and bracteas, but even from the leaves,
stipulas, or other parts. Linnzus and Artedi, there-

188 - OF THE INVOLUCRUM.

fore, were obliged to consider the znvolucra and in-
volucella, the former accompanying the general and
the latter the partial umbels, as a sort of calyx, and
the umbel altogether as one aggregate flower, com-
posed of florets united by a common radiated recep-
tacle. Consequently a cyme must be considered in
the same light ; nor are reasons wanting in support
of this hypothesis, which we shall consider after
having first explained all the parts of fructification.
In Euphorbia, however, the term bractea would
surely be more proper than zmvolucrum or involu-
cellum, as is evident from a consideration of the in-
florescence of the whole genus, so very different in
_ different species. In E. Peplis, and many others,
. the flowers are solitary and axillary; in others
again, as LE. amygdaloides, Engl. Bot. t. 256, and
Characias, t. 442, some flower-stalks are umbellate,
some scattered ; and the subdivisions of the umbel
in all are ultimately forked, that is, of a nature be-
tween umbellate and scattered. This genus. has,
moreover, a proper calyx or perianthium of a
most distinct and peculiar nature. Some species of
Anemone, a genus destitute of a perianthium, are
said by Linneus to have an involucrum, as A. Pul-
satilla, t. 51, for which the name of bractea might
be more correct, though in 4. Hepatica, Curt.
Mag. t. 10, it is placed so near the flower as
to seem a part of it, which, however, Is really not
the case.) . |

OF THE AMENTUM. 189

The name of Znvolucrum is applied by Gleditsch
to the membrane covering the fructification of ferns,
f- 144, 145; nor have I, in studying this part with
peculiar attention in order to reform the genera of
these plants, see Tracts relating to Natural His-
tory, p. 215, found reason to contrive any new
appellation. My learned friends Willdenow and
‘Swartz have judged otherwise, calling this mem-
brane the indusium, or covering; which seems to
me altogether superfluous. See its various forms in,
Engl. Bot. t. 1458—60, 1150, 1159, 1160, &e.

. Amentum, f. 146. Catkin, denominated by authors
before Linneus judus, nucamentum, or catulus; con-
sists of a common receptacle of a cylindrical form
beset with numerous scales, each of which is accom-
panied by one or more* stamens or pistils, so that
the whole forms an aggregate flower. The recep-
tacle itself and the bases of the scales are firmly
united, and the whole catkin falls off entire, except
that in some instances the upper part of each scale
withers away, as in the Willow genus, Salix, Engl.
Bot. t. 1388—90, 1402—4, &c., the seed-vessels
in that genus being quite distinct from the scales.
In others, the whole scale remains, enlarges, hardens,
and protects the seed, as in Pinus, the Fr tribe.
Such is the case with catkins of fertile flowers,
which are necessarily permanent till the seed is ripe;
barren ones fall as soon as the stamens have per-

190 OF THE SPATHA.

formed their office. Every catkin consists generally

of either one kind of flower or the other. ‘There are
few certain and invariable instances of stamens and
pistils in the same catkin, that circumstance occur-
ring chiefly in a few species of Salix and Carex;
nor 1s Typha, t. 1455—7, an exception to this.
Examples of barren-flowered catkins are seen, not
only in Salizv and Pinus, but in several plants whose
fertile or fruit-bearing flowers are not catkins, such
as the Walnut, and, unless I am much mistaken,
the Hazel-nut, ¢. 723. Each nut or seed of the
latter has a permanent coriaceous calyx of its own,
inadvertently calied by Gzertner an ¢volucrum,
though he considers the whole as an amentwum,
which this very calyx proves it not to be*. Humulus,
the Hop, ¢. 427, has a catkin for the fertile flower
only. |

4. Spatha, f. 147. Sheath, a covering which bursts
~ longitudinally, and is more or less remote from the
flower. This is exemplified in the Snow-drop,
Galanthus nivalis, Engl. Bot. t.19, the various
species of Narcissus, t. 17, 275 and 276, and the
Arum, t. 1298. The Spatha of the latter incloses
a Spadix, or elongated receptacle, common to many

* It appears moreover that Carpinus, the Hornbeam, has hitherto
erroneously been supposed to have an amentum for the fertile Hower.
The true nature of the covering of the seed, as well as of the common
stalk, proves it otherwise. | MP ane

OF THE GLUMA. 191

. flowers, according to the genuine Linnean idea of
this kind of calyx, taken from Palm-trees. In these
the Spadiv is branched.

5. Gluma, f. 148. Husk, the peculiar calyx of Grasses
and Grass-like plants, of a chaffy texture. These
husks are usually compressed, embracing each other
at the base, as in Phleum pratense, t. 1076. Some-
times they are depressed, flattened vertically, as in
Briza, t. 540 and 1316: To the husk belongs the
Arista, {. 149, Beard or Awa, a bristle-shaped ap-
pendage, usually spiral, and possessing the property
of an hygrometer. ‘This, however, is not always
present, even in different individuals of the same
species.

“ Unfortunately for the science,
On the awn there’s no reliance.”

So says, or rather sings, with more truth than subli-
mity, the ingenious author of the Mora Londinensis ;
fase. 6, t. 8.

The spiral kind of awn is most frequently attached
to the Corolla of grasses, which is precisely of the
same husky nature.as their calyx, and is, by some
botanists, considered as such. Specimens of glume
muticé, beardless husks, are seen in Phalaris cana-
riensis, Engl. Bot. t. 1310, and glume aristate,
‘awned ones, in Lagurus ovatus, t. 1334, and Stipa
pennata, t. 1356. ,

192 OF THE PERICHETIUM.

6. Perichetium, f. 150. A-scaly Sheath, investing
the fertile flower, and consequently the base of the
fruit-stalk, in some Mosses. In:the genus Hypnum
it is of great consequence, not only by its presence,
constituting a part of the generic character, but by
its differences in shape, proportion, and structure,
serving frequently to discriminate species. See Engl.
Bot. t. 1037—9, 1182, 1445—8, &c.; see also
the same part in Neckera, t. 1443, 4. Linneus
appears by his manuscripts to have intended adding

this to the different kinds of calyx, though it is not’
one of the seven enumerated in his printed works.
Nor is he, surely, correct in allowing it to the
genus Jungermannia. ‘The membranous part which
he there calls perzchetium is strictly analogous in-
deed to the calyptra, f..151, 152 b, or veil of real
mosses, esteemed by him a kind of calyx; but as I
presume with Schreber, to reckon it rather a corolla,
and Hedwig once thought the same, and as Junger-
mannia has more or less of a real calyx besides,
f. 152 a, see Engl. Bot. t. 771, &c., I would no
longer apply the term perzchetium to this genus at —
all. , |
The part called calyptra being removed from the
list, as being a corolla, the perichetium takes its
place among the seven kinds of calyx. We lay less
stress upon this coincidence than Linneus might
have done, when, according to the fashion of the
times, he condescended to distribute his immortal

ORIGIN OF THE CALYX. 195

Philosophia Botanica into 12 chapters and 365
sections, and reckoned seven parts of fructification
as well as seven species of calyx.

7. Volva, f. 153. Wrapper, or covering of the Fungus
tribe, of a membranous texture, concealing their
parts of fructification, and in due time bursting all
round, forming a ring upon the stalk, as in dgaricus
procerus, Sowerb. Fung. t. 190, and A. campestris,
the Common Mushroom, ¢. 305; such at least is |
the original meaning of this term, as explained in
the Phil. Bot.; but it has become more generally
used, even by Linnzus himself, for the more fleshy
external covering of some other Mungz, which is
scarcely raised out of the ground, and enfolds the
whole plant when young, f. 154. See Agaricus ©
wolvaceus, Sowerb. t. 1, and Lycoperdon fornicatum,
t. 198; also the very curious LZ. phalloides, t. 390,
now made a distinct genus by the learned Persoon,
under the name of Batarrea phalloides.

Linneus adopted from Cesalpinus the opinion that
the Calyx proceeded from the bark, like the leaves,
because of its similarity in colour and texture to those
organs. He even refined upon the original idea, and
supposed this part to proceed from the outer bark,
while the more delicate corolla originated in the liber.
What is now known of the physiology of the bark, as
explained in several of our preceding chapters, ren-
ders this hypothesis totally inadmissible.
O

194 OF THE COROLLA.

The knowledge of the real use of leaves, see chapter
16, may however throw some light upon that of the
calyx. Besides protection of the flower from external
injuries, which is one evident use of this part, it appears
highly probable that it may often contribute to the
growth and strength of the stalk which supports it, as
the leaves do to that portion of branch below them.
The stalk often swells considerably during the growth |
of the flower, especially just below the calyx, becoming
more woody, an alteration frequently necessary for the
support of the ripening fruit. When the calyx falls
very early, as in the Poppy tribe, Papaver and Glau-
cium, 1 cannot find that the flower-stalk is subsequently
enlarged, nor in any manner altered ; while in genera

“without number, whose calyx is permanent, the stalk
becomes not only more woody, but often considerably
thickened. ~

Ii. Corouxa. The Corolla, vulgarly called the leaves
of the flower, consists of those more delicate and
dilated, generally more coloured leaves, which are
always internal with respect to the calyx, and con-
stitute the chief beauty of a flower. In the Rose.
the Corolla is red and fragrant ; in the Violet pur-
pie; in the Primrose yellow.

This term includes two parts, the Petal, Petalum,
and the Nectary, Nectarium. The former is either
simple, as in the Primrose, in which case the Corolla
is said to be monopetalous, of one petal ; or com- —

FORMS OF THE COROLLA. 195

pound, as in the Rose, in which it is polypetalous,
of several. ‘The Nectary is sometimes a part cf
the petal, sometimes separate from if.

A monopetalous Corolla consists of two parts ;
the tube, ¢ubus, the cylindrical part inclosed in the
calyx of the Primrose ; and the limb, lamdus, which
is the horizontal spreading portion of the same
flower, f. 155. The analogous parts of a polype-
talous Corolla, as in the Wall-flower or Stock, f. 156,
are named the claw, unguis, f. 157 a, and the bor-
der, Zamina, b.*

The Corolla is infinitely diversified in form in
different genera, whence ‘Tournefort and Rivinus
derived their methods of arrangement. It is called
regular when its general figure is uniform, as in the
Rose, the Pink, the Columbine, Aguilegia vulgaris,
Engl. Bot. ¢. 297, and Gentiana Preumonanihe,
#.20; irregular when otherwise, as the Violet,
#. 619, 620, Dead-nettle, ¢. 768, and Lathyrus,
#805 and 1108. An equal Corolla, f- 156, is not
only regular, but all its divisions are of one size,
like those of the Primrose, f. 5, Campanula, 12,
or Sazifraga, t.9; an unequal one, f. 158, is when
some segments are alternately smaller than the
others, as in Butomus, ¢. 651, or otherwise diffe-
rent, as in Aguilegia, 1.297. It is by no means al-
ways necessary, in defining characters of genera, to
_ use these last terms, it being sufficient in general to
say that a Corolla is regular in opposition to one

O &

196 FORMS OF THE COROLLA.

that is irregular ; more especially as some species

of a genus may possibly have an equal corolla,

others an unequal one. |
The most usual shapes of a monopetalous co-

rolla are

campanulata, f- 159, bell-shaped, as in Campanula,
t.19.

infundibuliformis, f. 160, fannel-shaped, Pulmona-
ria, ¢. 118. |

hypocrateriformis, f. 155, salver-shaped, Primula,
t. 4.

rotata, wheel-shaped, that is, salver-shaped with
scarcely any tube, Borago, t. 36.

ringens, f. 161, ringent, irregular and gaping like
the mouth of an animal, Lamium, t.768 ; called
by former botanists /abcata, lipped.

personata, f. 162, personate, irregular and closed by
a kind of palate, Antirrhinum, t. 129.
Those of a polypetalous one are

cruciformis, f. 156, cruciform, regular and like a
cross, Dentaria, t. 309, and Cheiranthus, t. 469.

rosacea, rosaceous, spreading like a rose, Dryas,
t.451.

papilionacea, f. 163, papilionaceous, irregular and

spreading, somewhat like a butterfly, Lathy-
rus, t. 1108. ‘The various petals which compose |
such a flower are distinguished by appropriate
names, as vevillum, f. 164, standard, the large
one at the back; ale, f. 165, wings, the two

>

PHYSIOLOGY OF THE COROLLA. 197

side petals ; and carina, f. 166, the keel, consist-

ing of two petals, united or separate, embracing

the internal organs, f- 167. In Trifolium all the
petals are sometimes united into one at the lower
part.

zncompleta, incomplete, when parts, which analogy
would lead us to expect, are deficient, as in
Amorpha, a papilionaceous flower apparently, but
consisting of the vevdlum only ; or Rittera of
Schreber, 7. 168, a rosaceous one with a single
lateral petal, seeming as if four others had been
stripped off.

It is remarkable that irregular flowers sometimes
vary to regular ones on the very same plant, as
in Bignonia radicans, Curt. Mag. t. 485 ; > and
Antirr hinum Linaria, f. 169, Engl. Bot. t. —_
and 260.

Linnzus was of opinion that the Corolla originated

from the Liber or inner bark, as the Calyx from the

outer, but this cannot be defended now the real phy-
siology of the bark is better understood.

The whole use and physiology of the Corolla have
not yet been fully explained. ‘As a protection to the
tender and important parts within, especially from wet,
its use in many cases is obvious, but by no means in
all. Linneus imagined it to serve as wings, to waft
the flower up and down in the air, and so to promote
the functions of the Stamens and Pistils, as will here-
after be described ; nor is this opinion unfounded.

198 PILYSIOLOGY OF

Sprengel has ingeniously demonstrated, in some
hundreds of instances, how the Corolla serves as an
attraction to insects, indicating by various marks,
sometimes perhaps by its scent, where they may find
honey, and accommodating them with a convenient
resting-place or shelter while they extract it. This ele-
gant and ingenious theory receives confirmation from
almost every flower we examine. Proud man is dis-
posed to think that

“Full many a flower is born to blush unseen,”

because he has not deigned to explore it; but we find
that even the beauties of the most sequestered wilder-
ness are not made in vain. They have myriads of ad-
mirers, attracted by their charms, and rewarded with
their treasures, which very treasures would be as use-
less as the gold of a miser to the plant itself, were they
not thus the means of bringing insects about it. The
services rendered by such visitants will be understood
when we have described all the parts of a flower.
Besides the above purposes, I have always conceiv ed
the Corolla to fulfil some important office to the essen-
tial parts of the flower with respect to air, and espe-
cially light. It not only presents itself ina remarkable
manner to the sun-beams, frequently closing or droop-
- ing when they are withdrawn, but it is so peculiarly
distinguished by beauty or brilliancy of colour, that
one cannot but think its functions somewhat different
from those of the leaves, even with regard to light

THE COROLLA. » - 199

itself. Dr. Darwin calls the Corolla the lungs of the
stameis and pistils, and with great probability, for they
abound in air-vessels. But when we consider the ela-
borate and peculiar secretions of a flower, the elastic
inflammable pollen, the honey, and the exquisitely vo-
latile perfume, as we know frou: the curious discoveries
of modern chemistry how great a share light has in
the production of such, we cannot but conclude that
the petals must be of primary importance with respect
to their secretion by its means. .
Sometimes the Corolla is very short-lived; sometimes
very lasting, even till the fruit is perfected, though
mostly in a tadedcondition. In double flowers I have
observed it to be much more durable than in single
ones of the same species, as Anemonies and Poppies,
because, as I conceive, of its not having performed ts.
natural functions, the stamens and pistils of such
flowers being obliterated, or changed to petals ; hence
the vital principle of their corolla is not so soon ex-
hausted as usual. Phil. Trans. for 1788, p. 165.
The Corolla, as already mentioned, is not essenual.
Whatever its functions may be, they can be occasionally
performed by the Calyx perhaps, or even by the Fila-
ments of the Stamens; as those of leaves are, in leaf-
less plants, by the stems. When a flower has only
one covering, it is not always easy to say whether that
be a Calyx or Corolla. When green and coarse in
texture, like the former, we call it so, as in Chenopo-

200 DISTINCTIONS BETWEEN

dium, Engl. Bot. t. 1033, and 1721—4, and the na-
tura] relationship of this genus to Polygonum, t. 1044,
989, 756, &c., leads us to reckon the same part in
the latter a coloured calyx. On the other hand, when —
the part present is delicate and finely coloured, like
the generality of Corollas, we denominate it such ;
more especially if the plant to which it belongs be allied
to others that have a Calyx besides, as in Tudipa,
t. 63, allied to Leucojum, t. 621, which has a Spatha.
The great Jussieu denominates this part in the Tulip
and other liliaceous plants, however beautiful, a Calyx.
His definition of a Corolla is “ that covering of a flower
which is invested with the Calyx, deing very rarely
naked ; a continuation of the innner bark of the flower-
stalk, not of its cuticle; not permanent, but mostly
falling off from the stamens ; surrounding or crowning
the fruit, but never growing united with it; and having
its parts or segments for the most part alternate with -
the stamens, which are equal to them in number.”
By this rule the tube and six segments of a Narcissus,
t, 17, 275 and 276, constitute the Calyx, and then
surely what Jussieu calls a Crown, /. 1476, and Lin-
neus a Nectary, must be allowed the name of Corolla.
On the other hand, the Spatha becomes a Bractea.
Consequently the whole order of Liliaceous flowers in
general have a coloured Calyx only, which seems
hardly admissible; and yet I cannot conceal a recent
discovery which strongly confirms the opinion of my

COROLLA AND CALYX. 201

acute and candid friend. ‘Two species of a new genus”,
found by Mr. Menzies on the West coast of North
_ America, have beautiful liliaceous flowers like an 4ga-
panthus, with three internal petals besides! Tudbaghia
is a similar instance. I must however protest against
the idea of the Corolla originating exclusively from
the inner bark, as well as of the cuticle not being con-
' tinued over it, for reasons sufficiently apparent from
the former part of this work.

Itis a Linnean rule that the Stamens should be op-
posite to the segments of the Calyx, and alternate with
the parts of the Corolla. Its author nevertheless seems
of opinion that no absolute means of distinction be-
tween these two parts can be: pointed out, except
colour ; of the insufficiency of which he is aware. If
however the Corolla performs functions with respect
to light which the Calyx does not, and those functions
are indicated by its colour, a distinction founded on
such a principle is both correct and philosophical. We
must then conclude that in most liliaceous plants, not
in all, the two organs are united into one, and indeed
the outside is often green and coarse like a Calyx, the
inner coloured and delicate; witness Ornithogalum,
¢. 21, 130 and 499, Narthecium, t. 535, &c. Lin-
neus has the same idea respecting Daphne, t. 119
and 1381, and the analogy is confirmed by Gnidia,

* T have lately, ina paper to the Linnean Society, named this genus

Brodiza in honour of James Brodie, Esq. F.L.S. See Tr. of Linn.
Soc. v. 10. 1.

202 DISTINCTIONS BETWEEN COROLLAANDCALYX.

which is a Daphne with petals. In 7; rollius, t. 28,
and Helleborus, t. 200 and 6138, Linneus considers as
Petals what Jussieu, following Vaillant, thin ks a Calyx.
Of these plants we shall soon have occasion to speak.
again.

I cannot butconsideras a sort of Corolla the Calyptra
or Veil of Mosses, which Linneus reckoned a Calyx.
Schreber, very deep and critical in his inquiries con-
cerning these plants, and Hedwig, so famous for his
discoveries among them, were both of this opinion,
though the latter seems to have relinquished it. The
organ in question is a membranous hood, covering the
unripe fruit of these diminutive vegetables, like an
extinguisher, f- 151; but soon torn from its base, and
elevated along with the ripening capsule. See Lng.
Bot, t. 558, &c. The great peculiarity of this part,
whatever it be called, consists in its summit perform-
ing the office of a stigma, as Hedwig first remarked.
In Jungermannia, f: 159, t. 771, &c., the very same
part, differing only in usually bursting at the top to let
the fruit pass, is named by Linneus a perichetium,
but very incorrectly, as we have already hinted.

Whatever office the petals may perform with respect
to airand light, it is probable that the oblong summit
of the Spadix in drum, t. 1298, answers the same
purpose. When this part has been for a short time
exposed to the light, it assumes a purplish brown hue,
which M. Sennebier seems to attribute to the same
cause which he thinks produces the great heat ob-

OF THE NECTARY AND HONEY. 203. -

served in this flower, the rapid combination of oxygen
gas with the carbon of the plant; an hypothesis
hardly adequate to explain either.

Nectarium, the Nectary, may be defined that part
of the Corolla which contains or which secretes
honey. It is perhaps in effect nearly universal, as
hardly a flower can be found that has not more or less

_honey, though that liquor is far from being universally,
or even generally, formed by an apparatus separate
from the Petals. In monopetaious flowers, as Lamium
album, the Dead Nettle, ¢. 768, the tube of the corolla
contains, and probably secretes, the honey, without any
evident Nectary. Sometimes the part under considera-
tion is a production or elongation of the Coroila, as in
Violets; sometimes indeed of the Calyx, as in the Gar-
den Nasturtium, Zropeolum, Curt. Mag. t. 23 and
98, whose coloured Calyx, f#. 170, partakes much of
the nature of the petals. Sometimes it is distinct from
both, either resembling the petals, as in quilegia,

f- 171, Engl. Bot. t. 297, or more different, as in
Lipimedium, f. 172, 173, @. 438, Helleborus, t. 200
and 613, Aconitum, the cominon Monkshood, and
Delphinium, the Larkspur. Such at least is the mode
in which Linneus and his followers understand the
four last-mentioned flowers; but we have already
hinted that Jussieu is of a different opinion, and he

even calls the decided Nectary of Epimedium an in-

_ ternal petal! Difficulties attend both theories. It seems

paradoxical to call petals those singular bodies in

204 OF THE NECTARY

Aconitum, f. 174, like a pair of little birds, which are
manifestly formed only to hold the honey, and not
situated nor constructed so as to perform the proper
functions of petals; but on the other hand Ranun-
culus, Engl. Bot. t. 100, 515 and 516, one of the
same natural order, has evident calyx and petals,
which latter have a honey-bearing pore in their claw,
evincing their identity with the less petal-like Nectaries
just described. Other instances indeed of Nectaries
in the claws of petals are found in the Crown Imperial
and Lily ; which only confirms more strongly the com-
pendious construction of the Lily tribe, the leaves
of their flowers in these examples being Calyx, Petals
and Nectaries all in one.

The most indubitable of all Nectaries, as actually
secreting honey, are those of a glandular kind. In
the natural order of Cruciform plants, composing the
Linnean class Zetradynamia, these are generally four
green glands at the base of the Stamens. See Den-
taria, Engl. Bot, t. 309, Sisymbrium, twa2o, vane
Brassica, t. 6387. In Salix, t. 1488, and Geranium,
t. 322, 75, &c., similar glands are observable ; whilst
in Pelargonium, the African Geranium, the Nectary
is a tube running down one side of the flower-stalk. _

The elegant Parnassia, t. 82, of which we are
now acquainted with two new American species, has
a most elaborate apparatus called by Linneus Nectaries,
f. 175, but which the cautious Jussieu names Scales —
only. Linnaeus usually called every supernumerary

AND HONEY. 205

part of a flower Nectary, from analogy alone, though
he might not in every case be able to prove that such
parts produced honey. This is convenient enough for
botanical distinctions, though perhaps not always right
in physiology; yet there is nothing for which he has
been more severely and contemptuously censured.
He was too wise to answer illiberal criticism, or he
might have required his adversaries to prove that such
parts were not Nectaries. Sometimes possibly he may
seem to err, like L’Heritier, in calling abortive sta-
mens by this name. Yet who knows that their fila-
ments do not secrete honey, as well as the tubes of
numerous flowers? And though abortive as to An-
thers, the Filament, continuing strong and vigorous,
may do its office.

Honey is not absolutely confined to the fotrer:
The glands on the footstalks of Passion-flowers yield
it, and it exudes from the flower-stalks of some lili-
aceous plants.

The sweet viscid liquor in question has given rise
to much diversity of opinion respecting its use. Pon-
tedera thought it was absorbed by the seeds for their
nourishment while forming, as the yolk of the egg
by the chick. But Linneeus observes in reply, that
barren flowers produce it as well as fertile ones, witness
Urtica and Salix. In some instances the fertile flowers
only are observed to bear honey, as Phyllanthus and
Tamus, but such cases are rare. Even Darwin says
the honey is the food of the stamens and pistils, not

8)

=~

~

06 OF LS STAMENS AND ANTHERS.

recollecting that it is often lodged in spurs or cells

quite out of their reach.

There can be no doubt that the sole use of the

honey with respect to the plant is to tempt insects,

who in procuring it fertilize the flower, by- disturbing
the dust of the Stamens, and even carry that substance

from the barren to the fertile blossoms.

3,

Stamina. The Stamens, formerly called Chives,
are various in number in different flowers, from one
to some hundreds. ‘Their situation is internal with
respect to the parts we have been describing ; ee-

ternal to the Pistils, at least in simple flowers.

These organs are essential, there being no plant
hitherto discovered, after the most careful research,
that is destitute of them, either in the saine flower
with the pistils, or a separate one of the same
species.

A Stamen, f. 176, commonly consists of two
parts, the Filament, a, F2lamentum, and Anther, b*,
Anthera, the former being merely what supports the _
latter, which is the only essential part. Various
forms and proportions of Filaments may be seen
in the Tulip, where they are six In number, thick

_and short, Engl. Bot. t.63; the Pink, where they .

are ten, much more slender, and answering to the

:
* [ submit to the opinion of Professor Martyn in adopting this

word, for the reasons given in his Language of Botany, more espe-
cially as general practice seems to favour its use.

‘

OF THE POLLEN. 207

idea of a filament or thread, ¢. 62; and Anemone,
t. 51, where they are numerous.. They are com-
monly smooth, but sometimes, as in Verbascum,
f. 58, 59, bearded. In Melaleuca, ot. Bot.
¢. 36 and 50, they are branched ; and in Pruned(a,
Engl. Bot. t. 961, forked, one point only bearing
an Anther. In Aristolochia, t. 398, they are want-
ing, and nearly so in Potamogeton, t. 376, &c.
The Anther is the only essential part of a Stamen.
It is generally of a membranous texture, consisting
of two cells or cavities, bursting longitudinally at
their cuter edges, as in the Tulip. In Hvica, t. 1013
—15, it opens by pores near the summit, as in the
Potatoe-blossom Very rarely the Anther has four
cells, as ZYetratheca, Bot. of N. Holl. t. 5, and
Evot. Bot. t. 20*—22. Soinetimes it is ornamented
with a crest, as in many rice, and the genus
Pinus. See Mr. Lambert's splendid work.
The Pollen, or Dust, is contained in the Anther,
from which it is thrown out chiefly in warm dry
weather, when the coat of the latter contracts and
bursts. The Pollen, though to the naked eye a
fine powder, and light enough to be waited along
by the air, is so curiously formed, and so various
in different plants, as to be an interesting and
popular object for the microscope. ach grain of

* Jn this plate the engraver has by mistake expressed the section of
the anther, so as to look more like a germen, thongh the original
drawing was correct.

208 OF THE PISTILS.

\

it is commonly a membranous bag, round or an-—
gular, rough or smooth, which remains entire till
it meets with any moisture, being contrary in this
respect to the nature of the Anther; then it bursts
with great force, discharging a most subtile vapour.
In the Orchis family, and some other plants, the
pollen is of a glutinous nature, very different from its
usual aspect. See remarks on Mirabilis longifiora,
Ewot. Bot. v. 1. 44.

The Stamens are changed to petals in double
flowers, and rendered useless. ‘They are often ob-
literated by excessive nourishment, or when the
plant increases much by root, as in the Fiery Lily,
or true Lilium bulbiferum.

4, Pist1LLA. The Pistils, no less essential than the
Stamens, stand within them in the centre of the
flower, and are generally fewer. When in a_dif-
ferent flower, on the same or a different plant, they
are not always central. Linnzeus conceived them
to originate from the pith, and the stamens from
the wood, and hence constructed an ingenious hypo-
thesis, relative to the propagation of vegetables, which
is not destitute of observations and analogies to sup-
port it, but not countenanced by the anatomy and
physiology of the parts alluded to.

Each Pistil, f-177, consists of three parts. 1, the Ger-
men,a,or rudimentof the young fruit and seed, which
of course is essential ; 2, the Styus, b, style, various in

OF THE GERMEN. 209

length and thickness, sometimes altogether wanting,
and when present serving merely to elevate the
third part, Stzgma, c. This last is indispensable. Its
shape is various, either simple, scarcely more than a
point, or capitate, forming a little round head, or
variously lobed. Sometimes hollow, and gaping
- more especially when the flower is in its highest
perfection ; very generally downy, and always more
or Jess moist with a peculiar viscid fluid, which in
some plants is so copious as to form a large drop,
though never big enough to fall to the ground. The
moisture is designed for the reception of the pollen,
which explodes on meeting with it; and hence
the seeds are rendered capable of ripening, which,
though in many plants fully formed, they would not
otherwise be. : ,
The Germen appears under a variety of shapes
and sizes. It is of great moment for botanical di-
stinctions to observe whether it be superior, that is,
above the bases of the calyx and corolla, as in the
Strawberry and Raspberry ; or inferior, below them,
_as in the Apple and Pear.,Very rarely indecd the
Germen is supposed to be betwixt the calyx and
corolla, of which Sanguisorba, Engl. Bot. t. 1312,
is reckoned by Linnzus an example; but the co-
rolla there has really a tube, closely embracing the
Germen. In ddova, t. 453, the calyx is half in-
ferior, the corolla superior. When in botanical
language we say germen superior, it is equivalent
P

2°10 CHANGES IN THE PISTILS.

to flower inferior ; but it is sometimes more conve-
nient and proper, for the sake of analogy or unifor-
inity, to use one mode of expression than the other.
Pistils are sometimes obliterated, though oftener
changed to petals, in double flowers, as well as the
stamens; but I have met witha much more remark-
able change in the Double Cherry, of the pistil into
a real leaf, exactly conformable to the proper leaves
of the tree, only smaller. By this we may trace a
sort of round in the vegetable constitution. Begin-
ning at the herbage or leaves, we proceed insensibly
to bracteas in many species of Salvia, or to both
calyx and corolla in the Garden Tulip, which fre-
quently has a leaf half green half coloured, either in
the flower or on the stalk just below it. .4memone
alpina produces occasionally a petal among the
segments of its involucrum or bractea. Geum rivale,
Engl. Bot. t. 106, when cultivated in dry gravelly
ground, exhibits such tranformations in abundance.
Between petals and stamens there is evidently more
connection, as to their nature and functions, than
between any other organs, and they commonly
flourish and fall together. Yet only one instance is
known of petals changing to stamens, which Dr. _
Withering hascommemorated, in the Black Currant,
Ribes nigrum. On the other hand, nothing is more
frequent than the alteration of stamens to petals. —
Here then the metamorphosis begins to be retro-
grade, and itis still more so in the Cherry above men-

OF THE SEED-VESSEL AND ITS KINDS. @11

tioned, by which we return to the herbage again.—
The line of distinction seems to be most absolute
between stamens and pistils, which never change
into each other; on the contary, pistils, as we see,
rather turn into petals, or even into leaves.

. PERICARPIUM. The seed-vessel, extremely various
in different plants, is formed of the germen enlarged.
it is notan essential part, the seeds being frequently
-naked, and’ guarded only by the calyx, as in the
first order of the Linnean class Didynamia, of
which Lamium, Engl. Bot. t. 768, and Galeopsis,
t. 667, are examples; also in the great class of
compound flowers, Syagenesia, as well as in Rumer,
t. 724, Polygonum, t. 989, the Umbelliferous tribe,
numerous Grasses, &c. |

The use of the Seed-vessel is to protect the seeds
till ripe, and then in some way or other to promote
their dispersion, either scattering them by its elastic
power, or serving for the food of animals in whose
dung the seeds vegetate, or promoting the same
end by various other means. The same organ which
remains closed so long as it is juicy or moist, splits
and flies asunder when dry, thus scattering the seeds
in weather most favourable for their success. By an
extraordinary provision of Nature, however, in some
annual species of Mesembryanthemum, f.178, natives
of sandy desertsin Africa, the seed-vessel opens only |
in rainy weather ; otherwise the seeds might, in that

P@

912 THE CAPSULE AND ITS KINDS.

country, lie long exposed before they met _ suf-
ficient moisture to ——

1. Capsula, a Capsule, is a dry seed-vessel of a
woody, coriaceous or membranous texture, gene-
rally splitting into several valves; more rarely dis-
charging its contents by orifices or pores, as in

- Campanula and Papaver ; or falling off entire with
the seed. Internally it consists either of one cell or
several; in the latter case the parts which separate
the cells are called dissepimenta, partitions. The

central column to which the seeds are usually at-

~ tached is named columella. See Datura Stramo-
nium, f. 179, Engl. Bot. t. 1288.

Geertner, a writer of primary authority on fruits
and seeds, reckons several peculiar kinds of Cap-
sules; besides what are generally cael as
such; these are

Utriculus, a Little Bladder, which varies in thick-
ness, never opens by any valves, and falls off with
the seed. I believe it never contains more than one
seed, of which itis most commodiously, in botanical
language, called an external coat, rather than a
Capsule. Gertner applies it to Chenopodium, as
well as to Clematis, &c. In the former it seems a
Pellicula, in the latter a T esta, as we shall hereafter
explain. )

Samara is indeed a species of Capsule, of a com-
pressed form and dry coriaceous texture, with one

THE SILIQUA. 213

or two cells, never bursting, but falling off entire,
and dilated into a kind of wing at the summit or
sides. It is seen in the Elm, the Maple, the Ash,
Engl. Bot. t. 1692, and some other plants. This
‘term however may well be dispensed with, especially
as-it is the name of a genus in Linneus; an objec-
tion to which Cotyledon too is liable.

Folliculus, a Yollicle or Bag, reckoned by Linneus
a separate kind of seed-vessel from the Capsule,
ought perhaps rather to be esteemed a form of the
latter, as Gertner reckons it. This is of one valve
and one cell, bursting lengthwise, and bearing the _
seeds on or near its edges, or on a receptacle parallel
therewith. Instances are found in Vinca, t. 514,
Peonia, t. 1513, and Embothrium, Bot. of New
Fiolland, t. 7—10.

Coccum of Gertner, separated by him from cap-
sules, is a dry seed-vessel, more or less aggregate,
not solitary, whose sides are elastic, projecting the
seeds with great force, as in Euphorbia; also
Boronia, Tracts on Nat. History, t. 4—7. This
seems by no means necessary to be esteemed other-
wise than a sort of capsule:

2. Siligua, f- 180, a Pod, isalongdry solitary seed-vessel
of two valves, separated by a linear receptacle, along
each of whose edges the seeds are ranged alternately,
as in the class 7etradynamia. See Cheiranthus,
Engl. Bot. t. 462, and Cardamine, t. 803 also

214 THE LEGUMEN.

Bignonia echinata, figured by Gertner, ¢. 52, f- 1,
which, though cautiously called by him a capsula
siliquosa only, is as true a Siliqua, according to his
own definition, and every body’s ideas, as possible ;
so is also that of Chelidonium. He, justly indeed
names the fruit of Peona, capsula leguminosa, a
follicle with him being a single-valved capsule, with
the seeds marginal as in a Jegume.

Silicula, f. 181, a Pouch, is only a Pod of a short
or rounded figure, like Draba verna, Engl. Bet.
t. 586.

M5: Lecumen, f. 182, a Legume, is the peculiar solitary
_ fruit of the Pea kind, formed of two oblong valves,
without any longitudinal partition, and bearing the —
seeds along one of its margins only. See Engl. Bot.
t. 1046, 805, &c: The Tamarind is a Legume
filled with pulp, in which the seeds are lodged.
The Capsules of Helleborus and some other plants
allied thereto, justly indicated by Gertner as ap-
proaching very nearly to the definition of Legumes,
differ essentially in not being solitary, and in con-
sisting each but of one valve. Some Larkspurs in-
deed bear such capsules solitary, but analogy pele
us their true nature.
Whena Legume is divided sis several eaaax it is
- either by transverse constrictions, or by inflexion of —
‘the valves; never by a separate longitudinal parti-
tion; see Dolichos purpureus, Evot. Bot. t. 74.

-
‘

THE DRUPA, POMUM AND BACCA. 215

_ Sometimes, this kind of fruit lodges but one seed,
as in many species of Trifolium; see Engl. Bot.
t. 1048, also Viminaria denudata, Exot. Bot. t.27.

_ It is only by analogy that such are known to be
Legumes.

4, Drupa, f. 183, a Stone-fruit, has a fleshy coat, not
separating into valves, containing a single hard and
bony Nut, to which it is closely attached; as in the
Peach, Plum, Cherry, &c.; see Engl. Bot. t. 706
and 1383. The Cocoa-nut is a Drupa with a less
juicy coat. .

Sometimes the Nut, though not separating into
distinct valves, contains more than one cell, and
consequently several seeds. Instances are found
in Cornus, t.249, Gaertner, t. 26, and Olea, the
Olive, F/. Grec. t. 3, though one cell of the latter
is commonly abortive.

5. Pomum, f.184, an Apple, has a fleshy coat like
the Drupa, but containing a Capsule with several
_. seeds, as in common Apples and Pears; see Pyrus

domestica, t.350. :

This is comprehended by Ger tner under the dif-
ferent kinds of Bacca, it being sometimes scarcely
possible to draw the line between them; witness
the Linnean genus Sorbus. |

6. Bacca, f. 185, a Berry, is fleshy, without valves,

216 THE BACCA.

containing one or more Seeds, enveloped with pulp. _-
It becomes more juicy internally as it advances to
maturity, quite contrary-to the nature of a Capsule,
though the difference between these two unripe
fruits may not be discernible, and though some true
Berries, when fully ripe, finally become of a dry and
spongy texture: but they never open by valves or
any regular orifice. Examples of a Bacca are seen
in Atropa Belladonna, Engl. Bot. t. 592, and Ribes,
1289—92. ‘The same part in Hedera, t. 1267,
‘ ofa more mealy substance. In Cucubalus, t. 1577,
_ the coat only is pulpy. In Z7ientalis, t. 15, the
~ coat becomes very dry and brittle as soon as ripe,
and the cavity of the fruit is nearly filled by a glo-
bular columella. See Gaertner, t.50. |
Bacca composita, f. 186, a Compound Berry, con-
sists of several single ones, each containing a seed,
united together, as in Rubus, the Raspberry, Bram- :
ble, &c., Engl. Bot. t.715, 716, 826, 827. Each
of the separate parts is denominated an Acinus, or
Grain, which term Geertner extends to the simple
“many-seeded berries of the Vine, Gooseberry, &c.
The Orange and Lemon are true Berries, with a
thick coat. The Melon and Cucumber tribe have
_ a peculiar sort of Berry, for which Geertner uses
the name of Pepo, Gourd; and he defines it a Berry
whose cells, together with the seeds, are remote from.
the azis or centre, the seeds being inserted into
the sides of the fruit. . Passiflora suberosa, f. 187,

SPURIOUS KINDS OF BACC®. Q17

Hexot. Bot. t. 28, shows this insertion, being nearly
allied to the same tribe; but in this genus the pulp
invests each seed separately, — Acini withia
the common cavity.

Some fruits ranged by Linneus as Drupe with
many seeds, on account of the hardness of the shells
of those seeds, are best perhaps, on account of their
number, considered by Gertner as Bacce. Among
these are Mespilus, the Medlar.

There are several spurious kinds of berries, whose
pulp is not properly a part of the fruit, but originates
from some other organ. Thus, in the Mulberry, as.
well as the Strawberry-Spinach, Blitum, Curt. Mag.
t. 276, the Calyx after flowering becomes coloured
and very juicy, investing the seed, like a genuine
berry. The Corolla of Commelina Zanonia under-
goes a siinilar change, furming a black very juicy
coat to the capsule, being totally altered both in
shape and substance from its appearance in the
flower. In the Juniper, Engl. Bot. ¢. 1100, a few
scales of the fertile catkin become succulent, and
coalesce into a globular berry with three or more
seeds, to which Gertner applies the term galbulus,
the classical name of the Cypress fruit, which last
however is as true a strobilus or cone as that of the
Fir. In the Yew, ¢. 746, some have thought it a
calyx, others a peculiar kind of receptacle, which
becomes red and pulpy, embracing the seed. La-
marck has, in his Encyclopédie, v. 3. 228, consi-

18 | - THE STROBILUS.

dered this fruit as a real bacca or drupa, with the
idea or definition of either of which it cannot by
any means be made to accord, being open at the
top, and having no connection with the ‘stigma,
which crowns the seed itself. The same writer mis-
takes for a calyx the scales, which analogy shows

to be bracteas; and I cannot but think Jussieu and
Gertner more correct in their ideas of this singular
fruit, when they call the pulpy part in question a
receptacle, though the term calyx seems less para-
doxical, and is perhaps still more jusi*. We do not
know enough of ZYaxus nucifera to draw any con-
clusions from thence. See Gertner, t. 91. In the
Strawberry, Engl. Bot. t. 1524, what is commonly
called the berry is a pulpy receptacle, studded with
naked seeds. Inthe Fig, Gertner, t. 91, the whole '
fruit is a juicy calyx, or rather common receptacle,
containing 1n its cavity innumerable florets, each of
which has a proper calyx of its own, that becomes
pulpy and invests the seed, as in its near relation -
the Mulberry. The Paper Mulberry of China is
indeed an intermediate genus between the two, being

as it were a Fig laid open, but without any pulp in
the common receptacle. ;

7. Strobilus, f. 188, a Cone, is a Catkin hardened and
enlarged into a Seed-vessel, as in Pznus, the Fir.

* Hernandia, Gartn. t. 40, has a similar, though not succulent, calyx,

and the green cup of the Hazel-nut is equivalent to it.

THE SEEDS. 219

In the most perfect examples of this kind of fruit
~ the Seeds are closely sheltered by the scales as by a
capsule, of which the Fir, Cypress, &c., are instances.
In the Birch and Alder they have a kind of capsule
besides, and in the Willow and Poplar a stalked
bivalve capsule, still more separate from the scales.
The Plane-tree, Platanus, the Liguidambar and the
Comptonia, have globular catkins, in which bristles
or tubercles supply the place of scales. See
Gertner, t. 90.

. SEMINA. The Seeds are the sole “ end and aim

of all the organs of fructification. Every other part
is, in some manner, subservient to the forming, per-
fecting, or dispersing of these. _ Aseed consists of

several parts, some of which are more essential than

others, and of these I shall speak first.

Embryo, f. 2, 4, the Embryo, or Germ, is the
most essential of all, to which the rest are wholly
subservient, and without which no seed js perfect, or
capable of vegetation, however complete in external
appearance. Linneus, after Cesalpinus, names it
the Corculum, or Little Heart, and it is the point
~ whence the life and organization of the future plant
originate, as we have already explained, p. 74. In
* some seeds it is much more conspicuous than in

others. The Walnut, the Bean, Pea, Lupine, &c.,
show the Embryo in perfection. Its internal struc-
ture, before it begins to vegetate, is observed by

~

2

20 THE EMBRYO AND COTYLEDONS.

Geertner to be remarkably simple, consisting of an
uniform medullary substance, inclosed in its appro-
priate bark or skin. Vessels are formed as soon as_
the vital principle is excited to action, and parts are
then developed which seemed not previously to exist,
just as in the egg of a bird. In position, the Embryo
is, with respect to the base of the whole flower or
fruit, either erect, as in the Dandelionand other com-
pound flowers, reversed as in the Umbelliferous tribe,
or horizontal as in the Date Palm, /. 199,b,Gertner,
¢.9. In situation it is most commonly within the
substance of the seed, and either central as in Um-
belliferous plants, or excentric, out of the centre, as
in Coffee; in Grasses however it is external. Its
direction is either straight, curved, or even spiral, in
various instances. ‘The Embryo of seeds that havea
single cotyledon, or none at all, is peculiarly simple,
without any notch or lobe, and is named by peers
dimbryo monocots wong

Cotyledones, the Cotyledons; or Seed-lobes, are
immediately attached to the Embryo, of which they
form, properly speaking, a part. They are com-
monly twoin number, /.7; but in Prnus, and Dom-_
beya, the Norfolk Island Pine, they are more, {.3, as
already mentioned, p. 75. When the seed has sufti-
ciently established its root, these generally rise out of
the ground, and become a kind of leaves. Such is _
the true idea of the organs in question; but the same

OF THE ALBUMEN, OR WHITE. gat

name is commonly given to the body of the seed in
the Grass and Corn tribe, the Palms, and several
other plants, thence denominated monocotyledones,
because the supposed Cotyledon is single. ‘The
nature of this part we shall presently explain. It
neither rises cut of the ground, nor performs the
proper functions of a Cotyledon, for what these
plants produce is, from the first, a real leaf; or, if
_ the plant has no leaves, the rudiment of a stem, as
in Cuscuta. In either case, the part produced is
solitary, never in pairs; hence Gertner was misled
to reckon Cyamus Nelumbo, Ewot. Bot. t. 31, 39,
| among the monocotyledonous plants, the body of
its seed remaining in the earth, and the leaves spring-
ing one at a time from the Embryo, just as in the
Date Palm, Wheat, Barley, &e.

The Seed-lobes of Mosses, according to the obser-
vations of Hedwig, Mund. part 2. t.6, are above all
others numerous and subdivided, f: 195, 196, as
well as most distinct from the proper leaves; so that
these plants are very improperly placed by authors
aniong such as have no Cotyledons, a measure origi-
nating probably in theory and analogical reasoning
rather than observation. i

Albumen, the White, is a farinaceous, fleshy, or
horny substance, which makes up the chief bulk oi
some seeds, as Grasses, Corn, Palms, Lilies, never
rising out of the ground nor assuming the office of

299 OF THE VITELLUS,

leaves, being destined solely to nourish the germi-
nating embryo, till its roots can perform their office. —
In the Date Palm, /. 199, Gaertner, t. 9, this part is
nearly as hard asastone; in Mirabilis, Exot. Bot.
t. 23, itis like wheat flour. Itis wanting in several
tribes of plants, as those with compound, or with
cruciform flowers, and the Cucumber or Gourd
kind, according to Geertner. Some few leguminous
plants have it, and a great number of others which, .
like them, have cotyledons besides. We are not
however to suppose that so important an organ is
altogether wanting, even in the above-mentioned
plants. The farinaceous matter, destined to nourish
their embryos, is unquestionably lodged in their
cotyledons, whose sweet taste as they begin to ger-
minate often evinces its presence, and that it has
undergone the same chemical change as in Barley.
The Albumen of the Nutmeg is remarkable for its
eroded variegated appearance, and aromatic quality ;
the cotyledons of this seed are very small. |

Vitellus, the Yolk, first named and fully illus-
trated by Geertner, is less general than any of the
parts already mentioned. He characterizes it as very. |
firmly and inseparably connected with the Embryo,
yetnever rising out of the integuments of the seed
in germination, but absorbed, like the Albumen, for
the nourishment of the Embryo. If the Albumen
be present, the Vitellus is always situated between

OR YOLK. 295

it and the Embryo, and yet is constantly distinct
from the former. The Vitellus is esteemed by
Gertner to compose the bulk of the seed in Fauci,
Mosses and Ferns, as well as in the genus Zama,
Ff. 200, closely allied to the latter, see his ¢. 3, and
even in Ruppia, Engl. Bot. t. 136, and Cyamus.
In the natural order of Grasses the part under con-
sideration forms a scale between the Lmdbryo and
the Albumen.

I cannot but think that the Vitellus is nothing
else than a subterraneous Cotyledon. In the Horse
Chesnut and Garden Nasturtium, Geertner almost
allows, see his Introduction, p. 151, that they are
the same thing. It does not appear that any plant
with genuine ascending Cotyledons is likewise fur-
nished with this supposed organ; on the other hand,
it is commonly attributed to such as have the most
copious Albumen, and therefore should seem to
answer some other end than mere nutriment, which
is supplied by the latter. The reader may consult
Tr. of the Linn. Soc. v. 9. 204, where this subject
is fully discussed. It seems by Decandolle’s LV.
Franc.'v. 1. 157, that Mr. Correa has also exploded
the idea of a Vitellus in Bena but his reasons do
not appear.

We learn from the above i inquiries, that the old
distinction between plants with one Cotyledon and
those with several may still be relied on, though: in
the former the part which has commonly been so

224 TESTA, THE SKIN.

denominated is the Albumen, as in Corn, the real
Coiyledon of which is the scale or Vitellus, which
last organ however seems wanting in Palms, Lilies,
&c.. such having really no Cetyledon at all, nor
any thing that can perform its office, except the
stalk of their Embryo, which indeed may answer
the purpose of a Cotyledon, just as the stems of
many plants fulfil the office of leaves. In the Horse
Chesnut, Oak and Walnut possibly, whose seed-
lobes do not ascend, the functions of a real Coty-
ledon, as far as air is concerned, anc those of the
Albumen may be united in these lobes, as is the .
case with most Leguminous plants; which is ren-
dered more probabie, as several of the latter have
the corresponding parts likewise remaining under
ground. Hence the divided “ Vitellus,” as Gaertner
terms it, of the Cyamusis to be considered as a pair
of subterraneous Cotyledons, and the plant conse-
quently ranges near its natural allies the Poppy tribe,
as Mr. Salisbury, without the aid of physiology, has
shown in the Annals of Botany, v. 2. p. 70, 75.

Testa, f. 4, the Skin, contains all the parts of a
seed above described, giving them their due shape ;
for the skin is perfectly formed, while they are but

~a homogeneous liquid. This coat differsin thickness
and texture in different plants. It is sometimes
single, but more frequently lined with a finer and
_very delicate film, called by Gertner Membrana,

HILUM, THE SCAR. 225

as may be seen in a Walnut, and the kernel of a
Peach, Almond, or Plum. In the Jasmine a quan-
tity of pulp is lodged between the AZembrana and
the Testa, constituting a pulpy seed, semen bacca-
tum, which is distinct from the Acinus, or grain of
a compound berry in the Raspberry, the seed of the
latter having its proper double covering within the
pulp. The Zesta bursts regularly, and only from
the swelling of its contents In germination.

Hilum, the Scar, is the point by which the seed
is attached to its seed-vessel or receptacle, and
through which alone life and nourishment are con-
veyed for the perfecting its internal parts. Conse-
quently all those parts must: be intimately con-
nected with the inner surface of this scar, and they
are all found to meet there, and to divide or divari-
cate from that point, more or less immediately.
In describing the form or various external portions
of any seed, the lui is always to be considered
as the base. When the seed is quite ripe, the com-
munication through this channel is interrupted : it
separates from the parent plant without injury, a
Sear being formed on each. Yet the /iluim is so
far capable of resuming its former nature, that the
moisture of the earth is imbibed through it previous
to germination.
There are various accessory parts, or appendages,
Q ,

OF THE PELLICULA

to seeds, which come under the following denomi-
‘nations. | |

Pellicula, the Pellicle, called by Gertner Zpi-
dermis, closely adheres to the outside of some seeds,
so as to conceal the proper colour and surface of
their skin, and is either membranous, and often
downy, as in Convolvulus, or mucilaginous, not per-
ceptible till the seed is moistened, as in Salvia ver-
benaca, Engl. Bot. t.154. Perhaps the covering
of the seed in Chenopodium, called by Gertner
Utriculus, is merely a Pellicula.

Arillus, the Tunic, is either a complete or partial
covering of a seed, fixed to its base only, and more
orless loosely or closely enveloping its other parts.
Of this nature is the pulpy orange-coloured coat in

— Euonymus, Engl. Bot. t. 362, the beautiful scarlet
cup In Afselia, f 203, and the double membranous
cuat in Hippophiie, t.425, which last invests the
seed within the pulp of the berry. ‘The outer of
these coats only is described by Geertner, as a pe-
culiar membrane lining the cell of the berry; his
“entegumentum duplex” refers to the testa, which
I mention only to prevent misapprehension. The
Mace which envelops the Nutmeg is a partial dril-
lus, beautifully drawn in Geertner, ¢. 41.. Narthe-
cium, Engl. Bot. t.535, has a complete membra-
nous tunic, elongated beyond the seed at each end,
as in many of the Orchis tribe; and such seeds,

AND ARILLUS. 297

acquiring thence a light and chafly appearance, have
been denominated scodiformia, whence Bergius was
perhaps led, very unscientifically, to call the seeds
of ferns literally scobs or sawdust! An elastic pouch-
like Arillus, serving to project the seeds with con-
siderable force, occurs in Owalis, t. 762 and 1726.
In the natural order of Lutacee the same part,
shaped also like a pouch lining each cell of the cap-
sule, is very rigid or horny ; see Dictamnus albus,
or Fraxinella, Gertn. t.69, and Boronia, Tracts
on Nat. Hist. t. 4—7. Besides this coincidence,
there are many common points of affinity between
these plants and O.ralis, concerning colour, flavour,
habit, and structure. /agonia and its allies form
the connecting link between them, which Gertner
and Jussieu did not overlook. .We have pointed
eut this affinity in English Botany, p.762, and it is
confirmed by the curious circumstance of Jacquin’s
Ovalis rostrata, Oval. t. 22, having the very ap-
pendages to its filaments which make a peculiar
part of the character of Boronia. .

It is not easy to say whether the various, and fre-
quently elaborate, coat of the seed among the rough-
leaved plants, Borago, Anchusa, Lithospermum,
Cynoglossum, f. 201, Engl. Bot. t. 921, &e., should
be esteemed an Ari/lus or a Festa ; but the latter
seems most correct, each seed having only a simple
and very thin membranous internal skin besides.
Gertner therefore justly uses the term Nut for the

ae 3

998 PAPPUS, THE S8EED-DOWN.

seeds in question. ‘The same may be observed of —
Ranunculus, Myosurus, see Engl. Bot. t. 435,
Clematis, Anemone, &c., whose external coats are
no less various and elaborate ; yet such seeds are as
truly naked as those of the Didynamia class, figured
in Gertner, t. 66, each having a double skin and
10 more, which is one covering less than even the
genuine nut of the stone fruit, or of the Corylus.
In Geranium, Malva, &c., what has often been
called Arillus, is rather a kind of Capsule, not only
because their seeds have a double or even triple
skin, quite unconnected with this outer cover, but
because the latter is analogous to other Capsules.
The loose husky covering of the seed in Carex,
f- 202, is surely an Arillus. See Engl. Bot. also
the Rev. Mr. Wood’s observations on this genus in
Dr. Rees’s Cyclopedia, and Gertner, v. 1. 138.
‘This seed has besides a double esta, though most
of the true Grasses have but one, which in ground
Corn constitutes the bran, the husks of the blossom
being the chaff.

Pappus, the Seed-down, is restrained by Gerther
to the chaffy, feathery, or bristly crown of many
seeds that have no Pericarpium, and which origi-
nates from a partial calyx, crowning the summit of -
each of those seeds, and remaining after the flower
is fallen. Instances of this are the feathery appen-_
dages to the seeds of Dandelion, Engl. Bot. t. 510,

PAPPUS, THE SEED-DOWN. 229

and Goat’s-beard, ¢. 454, in which the part in que-
stion is elevated on a footstalk, f-204. In Car-
duus, or rather Cnicus, t. 974, 975, it 1s sessile,
though still feathery ; in real Carduus, ¢. 1112 and
973, bristly ; but in Cichorium, t. 539, consists of
mere chaffy teeth, more clearly evincing its affinity
to a Calyx. In Scadiosa it is double. In Budens,
t. 1113, 1114, the Pappus is formed of two, three
or four rigid barbed bristles. The use of this organ
is evidently to transport seeds to a distance from
their mative spot, either by resigning them to the
power of the wind, or by attaching them to the
shaggy coats of animals. In due time the crown
separates, and leaves the seed behind it, which hap-
pens sooner with the Thistle than most other plants.
Hence the vacant down of that genus is frequently
seen wafted in light masses over a whole country ;
which has not escaped the notice of poets.

The same term is used by the generality of bota-
nists for the feathery crown of seeds furnished with
a capsule, as Mpilobium, t. 1177, Asclepias, Cynan-
chum, &c., Gertn. t. 117, as well as for a similar
appendage to the base or sides of any seeds, as Salzer,
Engl. Bot. t. 183, 1403, Eriophorum, t. 873, &c.,
neither of which can originate from a Calyx. For
the former of these Geertner adopts the term Coma,
fer the latter Pubes, which last also serves for any
downiness or wocl about the Zesta of a seed} as in

230 OF THE CAUDA, ROSTRUM, ETC.

the Cotton plant, and Blandfordia nobilis, Evot.
Bot. t. 4.

Cauda, f. 205, a Tail, is an elongated, generally
feathery, appendage to some Seeds, formed of the
permanent style, as in Clematis, Engl. Bot. t. 612,
Dryas, t. 451, Geum, t. 1400.

Rostrum, a Beak, mostly applies to some elonga-
tion of a Seed-vessel, originating likewise from the
permanent style, as in Geranium, t. 272, Helleborus,
#. 200, though it is also used for naked seeds, as
Scandiv, f. 206, t. 1397.

Ala, f. 207, a Wing, is a dilated membranous
appendage to Seeds, as in Embothrium, Bot. of
N. Holl. t. 7. Banksia, Conchium, Bignonia echi-
nata, Gertn. t.52, Rhinanthus, Engl. Bot. t. 657,
serving to waft them along in the air. Geertner
wished to confine this term to a membranous ex-
pansion of the top or upper edge of a Seed or Seed-
vessel, using margo membranaceus for one that
surrounds the whole, but he has not adhered to it
in practice. Capsules are sometimes furnished with
one wing, as the Ash, oftener with several, as Halesva,
Acer, Begonia, &c. In Seeds the Wing is com-
monly solitary, except some Umbelliferous plants, —
as Thapsia, Garin. t. 21. |

APPENDAGES TO SEEDS. 931

Seeds are occasionally furnished with Spines,
Hooks, Scales, Crested appendages, particularly a
little gland-like part near the Scar, sometimes deno-
minated Strophiolum, as in Asarum, Gertn. t. 14,
Bossiea, Ventenat. Jard. de Cels, t.7, Platylobium,
Bot. of N. Holl. t. 6, Ulex, Spartium, &c. In
general however smoothness is characteristic of a
seed, by which it best makes its way into the soft
earth, though sometimes it is barbed, or at least its
covering, as in Stipa, Engl. Bot. t. 1356, that it
may not easily be withdrawn again by the powerful
feathery appendage of that plant,which, after having
by its circumvolutions forced the seed deeper and
deeper, breaks off at a joint, and flies away.

The various modes by which seeds are dispersed
cannot fail to strike an observing mind with admira-
tion. Who has not listened in a calm and sunny
day to the crackling of Furze bushes, caused by the
explosion of their little elastic pods; nor watched
the down of innumerable seeds floating on the sum-
mer breeze, till they are overtaken by a shower,
which moistening their wings stops their further
flight, and at the same time accomplishes its final
purpose, by immediately promoting the germination
of each seed inthe moistearth? How little are chil-
dren aware, as they blow away the seeds of Dande-
lion, or stick Burs in sport upon each other’s clothes,
that they are fulfilling one of the great ends of
Nature! Sometimes the’Calyx, beset with hooks,

232 THE RECEPTACLE.

forms the bur, as in Arctium Lappa, Engl. Bot.
t. 1228; sometimes hooks encompass the fruit itself,
as in Xanthium, and some species of Galium, parti-
cularly G. Aparine, t. 816. Plants thus furnished
are observed by Linnzeus to thrive best in a rank
mauured soil, with which, by being conveyed to the
dens of wild animals, they are most likely to meet.
The Awns of grasses answer the same end. Pulpy
fruits serve quadrupeds and birds as food, while
their seeds, often small, hard and indigestible, pass
uninjured through the intestines, and are deposited
far from their original place of growth, in a condition
peculiarly fit for vegetation. LEven such seeds as are
themselves eaten, like the various sorts of nuts, are
hoarded up in the ground and occasionally forgotten,
_ or carried to a distance, and in part only devoured.
The ocean itself serves to waft the larger kinds of
seeds, from their native soil to far-distant shores.

7. RecerpracuLuM. The Receptacle is the common
base or point of connexion of the other parts ot
fructification. Itis not always distinguishable by
any particular figure, except in compound flowers
constituting the Linnean class Syngenesia, in which
itis very remarkable and important. In the Daisy,
Sf: 208, Engl. Bot. t. 424, itis conical; in Chry-
santhemum, t. 601, convex ; in others flat, or slightly
concave. Picris, t. 972, has it naked, that is, desti-
tute of any hairs or scales between the florets or

VARIOUS KINDS OF FLOWERS. 233

seeds ; Carduus, t. 1112, hairy ; Anthemis, t. 602,
scaly; and Onopordum, t. 977, cellular like a
honey-comb, f. 209. On this and the seed-down
are founded the most solid generic characters of
these plants, admirably illustrated by the inimitable
Gertner. )
~ The term Receptacle is sometimes extended by
- Linnzus to express the base of a flower, or even its
internal part between the stamens and pistils, pro-
vided there be any thing remarkable in such parts,
without reference to the foundation of the whole
fructification. It also expresses the part to which
the seeds are attached in a seed-vessel, and the
common stalk of a spike, or spikelet, in grasses.

ee

Having thus explained the various organs of fructi-
fication, we shall add a few remarks concerning flowers
in general, reserving the functions of the Stamens and
Pistils, with the Linnean experiments and inquiries
relative to that curious subject, tor the next chapter.

A flower furnished with both calyx and corolla is
called flos completus, a complete flower; when the
latter is wanting, zcompletus; and when the corolla
is present without the calyx, nwdus, naked. When the
stamens and pistils are both, as usual, in one flower,
that flower is called perfect, or united ; when they are
situated in difterent flowers of the same species, such I
would call separated flowers; that which has the

234 COMPOUND FLOWERS.

stamens being named the barren flower, as producing
no fruit in itself, and that with pistils the fertile one,
as bearing the seed. If this separation extends no
further than to different situations on the same indi-
vidual plant, Linnzeus calls such flowers monoici, mo-
noecious, as confined to one house or dwelling; if the
barren and fertile lowers grow from two separate roots,
they are said to be dioici, dicecious. Some plants have
united flowers and separated ones in the same species,
either from one, two or three roots, and such are
called polygamous, as making a sort of compound —
household. si

A Compound flower consists of numerous florets,
Htoscult, all sessile on a common undivided Receptacle,
and inclosed in one contiguous Calyx or Peranthium.
It is also essential to this kind of flower that the An-
thers. should be united into a cylinder, to which only
the genus Zussilago affords one or two exceptions,
and AKwhnia another; and moréover, that the stamens
should be five to each floret, Srgesbeckia flosculosa of
L’Heritier, Sterp. Nov. t. 19, alone having but three.
The florets are always monopetalous and superior,
each standing on a solitary naked seed, or at least the
rudiments of one, though not always perfected. Some
Compound flowers consist of very few florets,as Humea
elegans, Evot. Bot. t. 1, Prenanthes muralis, Engt.
Bot. t. 457; others of many, as the Thistle, Daisy,
Sunflower, &c. The tlorets themselves are of two
kinds, digudati, ligulate, shaped like a strap or ribband,

AGGREGATE FLOWERS. 935

f, 210, with three or five teeth, as in Tragopogon,
t. 434, and the Dandelion ; or ¢wdu/osi, tubular, cylin-
drical and five-cleft, as in Carduus, t. 1112, and Tana-
cetum, t. 1229. The marginal white florets of the
Daisy, f- 211, are of the former description, and com-
pose its radius, or rays, and its yellow central ones
come under the latter denomination, f. 212, consti-
tuting its discus, or disk. ‘The disk of such flowers is
most frequently yellow, the rays yellow, white, red, or |
_ blue. No instance is known of yellow rays with a
white, red, or blue disk.

An Aggregate flower has a common undivided Re-
ceptacle, the Anthers all separate and distant, Jaszone
only, Engl. Bot. t. 882, having them united at the
base, but not into a cylinder, and the florets commonly
stand on stalks, each having a single or double partial
calyx. Such flowers have rarely any inclination to
yellow, but are blue, purple, or white. Instances are
found in Scabiosa, t. 659 and 1311, Dipsacus, t. 1032
and 877, and the beautiful Cape genus Protea.

Such is the true idea of an Aggregate flower, but
Linneeus enumerates, under that denomination, seven
kinds, his favourite number: these are,

1. The Aggregate flower properly so called, as just
mentioned.

2. ‘The Compound flower previously described.

3. The Amentaceous flower, or Catkin, of which we
have spoken, p. 189.

236 AGGREGATE AND

4. The Glumose, or Chaffy flower, peculiar to the
Grasses, see p. 191.

5. The Sheathed flower, whose common receptacle
springs from a Sheath, as in drum.

6. The Umbellate; and

7. The Cymose flowers, concerning which two last a |
few observations are necessary.

Linneus and his friend Artedi thought the great
natural umbelliferous order could not be divided into
good and distinct genera by the seeds or parts of the
flower, without taking into consideration the. general
and partial involucral leaves, which they therefore
chose-to consider as a part of the fructification, and
defined as a calyv remote from the flower. ‘The rays
of the umbel, of course, became the subdivisions of a
branched receptacle, and the whole umbel was consi-
dered as one aggregate flower. It necessarily followed
that a Cyme, see p. 180, must be considered in the
same light; nor did the sagacity of Linnzus overlook
the arguments in favour of this hypothesis. -Many of
the umbelliferous tribe, as ZZeracleum, t. 939, Cau-
calis Coriandrum, &c., have their marginal flowers
dilated, radiant, and more or less inclined to be imper-
fect or abortive, thus evincing an analogy with real
compound flowers like the Sunflower, which analogy
is still more striking between Ocnanthe, ¢. 363, 347,
348, and the Marigold, Calendula. So the cymose
plants, as Viburnum Opulus, t. $32, bear dilated and

COMPOUND FLOWERS. 237

abortive marginal flowers, and Hydrangea hortensis,
Sm. Ic. Pict. t. 12, has scarcely any others. Cornus
sanguinea, Engl. Bot. t. 249, has a naked cyme,

C. Suecica, t. 310, an umbel accompanied by coloured
bracteas, or,as Linnzus judged, acoloured nvolucrum,

proving the close affinity between these two modes of
inflorescence.

Notwithstanding all this, I presume to dissent from
the above hypothesis, as offering too great violence to
Nature, and swerving from that beautiful and philoso-
phical Linnzan principle, of characterizing genera by
the fructification alone; a principle which those who
are competent to the subject at all, will, I believe, never
find to fail. The seeds and flowers of the umbelliferous
family are quite sufficient for our purpose, while the
_involucrum is very precarious and changeable; often
deficient, often immoderately luxuriant, in the same
genus. In the cymose plants every body knows the
real parts of fructification to be abundantly adequate,
the involucrum being of small moment; witness that
most natural genus Cornus. For all these, and other
reasons, to particularize which would lead me too far,
I have, p.-179, reckoned the Umbel and Cyme modes
of flowering, and not themselves aggregate flowers.

CHAPTER XxX.

OF THE PECULIAR FUNCTIONS OF THE STAMENS
AND PISTILS, WITH THE EXPERIMENTS AND OB-
SERVATIONS OF LINNEUS AND OTHERS ON THAT
SUBJECT.

Tue real use of the Stamens of Plants was long a
subject of dispute among philosophers, till Linneeus,
according to the general opinion at present, explained
it beyond a possibility of doubt. Still there are not
wanting persons who from time to time start objec-
tions, prompted either by a philosophical pursuit of
truth, or an ambitious desire of distinguishing them-
selves in controverting so celebrated a doctrine, as
some have written against the circulation of the animal
blood. I propose to trace the history of this doctrine,
and especially to review the facts and experiments
upon which Linneus founded his opinion, as well as
the objections it has had to encounter. It would be
endless, and altogether superfluous, to bring forward
new facts in its support, nor shall I do so, except
where new arguments may render such a measure ne-
cessary.

The Stamens and Pistils of flowers have, from the
most remote antiquity, been considered as of great 1m-
portance in perfecting the fruit. The Date Palin, from

FUNCTIONS OF STAMENS AND PISTILS. 239

time immemorial a primary object of cultivation in the
more temperate climates of the globe, bears barren and
fertile flowers on separate trees. The ancient Greeks
soon discovered that in order to have abundant and
well-flavoured fruit, it was expedient to plant both trees
near together, or to bring the barren blossoms to those
which were to bear fruit; and in this chiefly consisted
the culture of that valuable plant. ‘Tournefort tells us
that without such assistance dates have no kernel, and
are not good food. ‘The same has long been practised,
and is continued to this very day in the Levant, upon
the Pistacia, and the Fig.

At the revival of learning botanists were more occu-
pied in determining the species, and investigating the
medical properties of plants, than in studying their
physiology; and when after a while the subject in
question was started, some of them, as Morison, Vour-
nefort and Pontedera, uniformly treated with great
contempt the hypothesis which has since been esta-
blished. We shall, as we proceed, advert to some cf
their arguments. |

About the year 1676, Sir Thomas Millington,
Savilian Professor at Oxford, is recorded to have hinted
to Dr. Grew that the use of the Stamens was probably
to perfect and fertilize the seed. Grew adopted the
idea, and the great Ray approved it. Several other-
botanists either followed them, or had previously con-
ceived the same opinion, among which R. J. Camerarius,
Professor at Tubingen towards the end of the seven-

'

940 - FUNCTIONS OF

teenth century, was one of the most able and original.
Vaillant wrote an excellent oration on the subject,
which being hostile to the opinions of Tournefort, lay
in obscurity till published by Boerhaave. Blair and
Bradley assented in England, and several continental
botanists imbibed the same sentiments. Pontedera,
however, at Padua, an university long famous, but then
on the decline, and consequently adverse to ail new
inquiry and information, in 1720 published his n-
thologia, quite on the other side of the question.
Linnzus, towards the year 1732, reviewed all that
had been done before him, and clearly established the

fact so long in dispute, in his Lwndamenta and Philo- —

sophia Botanica. He determined the functions of the
Stamens and Pistils, proved these organs to be essential
to every plant, and thence conceived the happy idea of
using them for the purpose of systematical arrangement.
In the latter point his merit was altogether original; in
the former he made use of the discoveries and remarks
of others, but set them in so new and clear a light, as
in a manner to render them his own.

We have already mentioned, p. 106, the two modes

by which plants are multiplied, and have shown the

important difference between them. Propagation by
seed is the only genuine reproduction of the species,

and it now remains to prove that the essential organs

of the flower are indispensably requisite for the per-
fecting of the seed.

oo

bili one must have observed that the flower oft a)

STAMENS AND PISTILS. 24)

plant always precedes its fruit. To this the Meadow
Saffron, Enyg/. Bot. ¢. 133, seems an objection, the
fruit and leaves being perfected in the spring, the
blossoms not appearing till autumn; but a due exami-
nation will readily ascertain that the seed-bud formed
in autumn is the very same which comes to maturity
in the following spring. A Pine-apple was once very
unexpectedly cited to me as an instance of fruit being
formed before the flower, because the green fruit in
that instance, as in many others, is almost fully grown
before the flowers expand. ‘The seeds however, the

essence of the fruit, are only inembryo at this period,
just as in the germen of an Apple blossom.

It was very soon ascertained that flowers are invari-
ably furnished with Stamens and Pistils, either in the
same individual, or two of the same species, however
defective they may bein other parts; of which Aippuris,
Engl. Bot. t. 763, the most simple of blossoms, is a
remarkable example. Few botanists indeed had de-
tected them in the Lemua or Duck-weed, so abundant
on the surface of still waters, and Valisneri alone fora
long time engrossed the honour of having seen them.
In our days however they rewarded the researches of
the indefatigable Ehrhart in Germany, and, on being
sought with equal acuteness, were found in England.
Three species have been delineated in Engl. Bot.

“t. 926, 1095 and 1233, from the discoveries of Mr.
Turner and Mr. W. Borrer. The flowers of Mosses,
long neglected and afterwards mistaken, were faithfully

R -

249 FUNCTIONS OF

delineated by Micheli, carefully examined and properly
understood by Linnzus as he rambled over the wilds
of Lapland, and at length fully illustrated, and placed
out of all uncertainty, by the justly celebrated Hedwig.
These parts indeed are still unknown in ferns, or at
least no satisfactory explanation of them has reached
me, though the seeds and seed-vessels are sufficiently
obvious.

The existence of the parts under consideration is so
incontrovertible in every flower around us, that Ponte-
dera was reduced toseek plants without stamens among
the figures of the Hortus Malabaricus; but the plates
in which he confided are now known to be faulty in
that very particular.

Plants indeed have occasionally abortive stamens in
one flower and barren pistils in another, and the Plan-
tain-tree, Musa, is described by Linnzus as having five
out of its six stamens perfected in such blossoms as
ripen no fruit, while those with a fertile germen con-
tain only a single ripe stamen, five being ineffective.
This only shows the resources, the wisdom, and the
infinite variety of the creation. When the roots are
Inxuriantly prolific, the flowers are in some measure
defective, Nature, relaxing as it were from her usual
solicitude, and allowing her children to repose, and
indulge in the abundance of good things about them.
But when want threatens, she instantly takes the alarm ;

* This hitherto unknown fact appears in his Tour through that
country, lately published in English, v. 1. 185. -

STAMENS AND PISTILS. 943

all her energies are exerted to secure the future pro-
geny, even at the hazard of the parent stock, and to
send them abroad to colonise more favourable situa-
tions.

Most generally the access of the pollen is not trusted
to any accidental modes of conveyance, however nu-
merous, elaborate, and, if we may so express it, In-
genious, such modes may be; but the Stamens are for
greater security lodged in the same flower, under the
protection of the same silken veils, or of more sub-
stantial guards, which shelter their appropriate pistils.
This is the case with the majority of our herbs and
shrubs, and even with the trees of hot countries, whose
leaves being always present might impede the passage
of the pollen. On the contrary, the trees of cold
climates have generally separated flowers, blossoming
before the leaves come forth, and in a windy season
of the year; while those which blossom later, as the
Oak, are either peculiarly frequented by insects, or,
like the numerous kinds of Fir, have leaves so little
in the way, and pollen so excessively abundant, that
impregnation can scarcely fail. |

The pollen and the stigma are always in perfection
at the same time, the latter commonly withering and
falling off a little after the anthers, though the style
may remain, to become an useful appendage to the
fruit. The Viola tricolor or Pansy, the Gratiola, the
Martynia, and many plants besides, have been ob-—
served to be furnished with a stigma gaping only at

R Q

944 FUNCTIONS OF

the time the pollen is ripe. The beautiful Jacobean
Lily, Amaryllis formosissima, Curt. Mag. t. 47,
justly described by Linneus as provided with a drop
of clear liquid, which protrudes every morning from
the stigma, and about noon seems almost ready to fall
to the ground. It is however reabsorbed in the after-
noon, having received the pollen whose vapour renders
it turbid, and whose niinute husks afterwards remain
upon the stigma. The same phenomenon takes
place several successive days.

In opposition to similar facts, proving the synchro-
nous operation of these organs, Pontedera has, with
more observation than ustial, remarked that in the
umbelliferous tribe the style frequently does not ap-
pear till the anthers are fallen. But he ought to have
perceived that the stigma is previously perfected, and
that the style grows out afterwards, in a recurved and
divaricated form, for the purpose of providing hooks
to the seeds. ‘Itis also observable that in this family
the several organs are sometimes brought to perfection
in different flowers at different times, so that the an-

thers of one may impregnate the stigmas of another .

whose stamens. were abortive, or long since withered.
The same thing happens in other instances. Linneus
mentions the Jatropha urens as producing flowers
with stamens some weeks in general before or after
the others. Hence he obtained no seed, till he pre-
served the pollen for a montli or more in paper, and
scattered it on a few stigmas then in pefection. ‘There

STAMENS AND PISTILS. Q45

can be no doubt that, in a wild state, some or other
of the two kinds of blossoms are ripe together, through-
out the flowering season, on different trees.

A similar experiment to that just mentioned was
made in 1749 upon a Palm-tree at Berlin, which for
want of pollen had never brought any fruit to perfec-
tion. A branch of barren flowers was sent by the
post from Leipsic, twenty German miles distant, and
suspended over the pistils. Consequently abundance
of fruit was ripened, and many young plants raised
from the seeds*.

Tournefort and Pontedera supposed the pollen to

_be of an excrementitious nature, and thrown off as
superfluous. But its being so curiously and distinctly
organized in every plant, and producing a peculiar
vapour on the accession of moisture, shows, beyond
contradiction, that it has functions to perform after it
has left the anther. The same writers conceived that
the stamens might possibly secrete something to cir-
culate from them to the young seeds; an hypothesis

J F ait as P

* What species of Palm was the subject of this experiment does
not clearly appear. In the original communication to Dr. Watson,
printed in the preface of Lee’s Introduction to Botany, it is called
| Palma major foliis flabelliformibus, which seems appropriate to Rhapis
flabelliformis, Ait. Hort. Kew. 2. 3. 473; yet Linneus, in his Dis-
sertation on this subject, expressly calls it Phanir dactyhifera, the
Date Palm, and says he had in his garden many vigorous plants
raised from a portion of the seeds above mentioned. The great suc-

cess of the experiment, and the “ fan-shaped” leaves, make me rather
take it for the Rhapis, a plant not well known to Linneus.

-

246 FUNCTIONS OF

totally subverted by every flower with separated organs,
whose stamens could circulate nothing to germens on
a different branch or root; a difficulty which the judi-
cious Tournefort perceived, and was candid enough
to allow. |

Both the conjectures just mentioned vanish before
one luminous experiment of Linnzus, of all others
the most easy to repeat and to understand. He re-
moved the anthers from a flower of Glaucium phenc-
-ceum, Engl. Bot. .t. 1433, stripping off the rest of
that day’s blossoms. Another morning he repeated
the same practice, only sprinkling the stigma of that
blossom, which he had last deprived of its own sta-
mens, with the pollen from another. ‘The flower first
mutilated produced no fruit, but the second afforded
very perfect seed. ‘ My design,” says Linnzus,
“was to prevent any one in future from believing that
the removal of the anthers from a flower was in itself
capable of rendering the germen abortive.”

The usual proportion and situation of stamens with
respect to pistils is well worthy of notice. ‘The for-
mer are generally shortest in drooping flowers, longest
in erect ones. ‘The barren blossoms stand above the
fertile ones in Carex, Coix, Arum, &c., that the pollen
may fall on the stigmas. This is the more remark-
able, as the usual order of Nature seems in such
plants, as well indeed as in compound and even um-
belliferous flowers, to be reversed, for the pistils are

STAMENS AND PISTILS. 247

invariably central, or internal, in every simple flower,
and would therefore, if drawn out into.a moncecious
spike, be above the stamens.

Many curious contrivances of Nature serve to bring
the anthers and stigmas together. In Gloriosa, Andr.
Repos. t. 129, the style is bent, at a right angle from
the very base, for this evident purpose. In Savifraga,
and Parnassia, Engl. Bot. t. 82, the stamens lean
one or twoat atime over the stigma, retiring after
they have shed their pollen, and giving place to others ;
which wonderful ceconomy is very striking in the
garden Rue, Ruta graveolens, whose stout and firm
filaments cannot be disturbed from the posture in which
they may happen to be, and evince a spontaneous
movement unaffected by external causes. The five
filaments of the Celosia, Cock’s-comb, are connected
at their lower part by a membranous web, which in
moist weather is relaxed, and the stamens spread for
shelter under the concave lobes of the corolla. When
the air is dry the contraction of the membrane brings
them together, to scatter their pollen in the centre of
the flower. The elastic filaments of Parietaria, Engl.
Bot. t.879, for a while restrained by the calyx, as
those of the lovely Kalmie, Curt. Mag. t. LZ 5y AZ,
are by the minute pouches in the corolla, relieve them-
selves by an elastic spring, which in both instances
serves to dash the pollen with great force upon the
stigma. The same end is accomplished by the curved
germen of Medicago falcata, Engl. Bot. t. 1016,

948 OF THE BARBERRY.

releasing itself by a spring from the closed keel of the
flower.

But of all flowers that of the Barberry-bush, ¢. 49,
is most worthy the attention of a curious physiologist.
In this the six stamens, spreading moderately, are
sheltered under the concave tips of the petals, till —
some extraneous body, as the feet or trunk of an in-
sect in search of honey, touches the inner part of each
filament near the bottom. The irritability of that part
is such, that the filament immediately contracts there,
and consequently strikes its anther, full of pollen,
against the stigma. Any other part of the filament
may be touched without this effect, provided no con-
cussion be given to the whole. After a while the fila-
ment retires gradually, and may again be stimulated;
and when each petal, with its annexed filament, is
fallen to the ground, the latter on being touched shows
as much sensibility as ever. See Zyacts on Nat. His-
tory, 165. I have never detected any sympathy be-
tween the filaments, nor is any thing of the kind ex-
pressed in the paper just mentioned, though Dr.
Darwin, from some unaccountable misapprehension,
has quoted me to that effect. It is still more wonderful
that the celebrated Bonnet, as mentioned in Sennebier’s
Physiologie Végétale, v. 5. 105, should have observed
this phenomenon in the Barberry so very inaccurately
as to compare it to the relaxation of a spring, and that
the ingenious Sennebier himself, in quoting me, p. 103,
for having ascertained the lower part only of each

OF THE BARBERRY. 249

filament to be irritable, should express himself as fol-
lows: ‘It has not yet been proved that the movement
of the stamens is attended with the contraction of the
filaments; which nevertheless was the first proof neces-
sary to have been given in order to ascertain their ir-
ritability ; it is not even yet well known which is the
irritable part of the filaments, and whether it be only
their base, as Smith has had the address to discover.”
In answer to which I need only request any one to
read the above account, or the more ample detail in my
original paper, and above all, to examine a Barberry-
blossom for himself; and if any doubts remain con-
cerning the existence of vegetable irritability, let him
read Sennebier’s whole chapter intended to disprove
it, where that candid philosopher, while he expresses
his own doubts, has brought together every thing in
its favour. Among the whole of his facts nothing is
more decisive than the remarks of Coulomb and Van
Marum on the Luphorbia, whose milky juices flow so
copiously from a wound, in consequence of the evi-
dent irritability of their vessels ; but when the life of
the plant is destroyed by electricity, all the flowing is
at anend. Itis superfluous to add any thing on this
subject, and I return to that of the impregnation of
flowers.

I have already mentioned that any moisture causes
the pollen to explode, consequently its purpose is
hable to be frustrated by rain or heavy dews. Lin-
neeus observes that husbandmen find their crops of

250 PROTECTION OF THE POLLEN.

rye to suffer more from this cause than barley, because
in the latter the anthers are more protected by the
husks; and the Juniper berries are sparingly, or not
at all, produced in Sweden when the flowering season
has been wet. ‘The same great observer also remarks,
what yearly experience confirms, that Cherry-trees are
more certainly fruitful than Pear-trees, because in the
former the opening of the anthers is, in each blossom,
much more progressive, so that a longer period elapses
for the accomplishment of the fertilization of the ger- -
men, and there is consequently less chance of its being
hindered by a few showers.

To guard against the hurtful influence of rasinaal
dews or drenching rains, most flowers either fold their
petals together, or hang down their heads, when the
sun does not shine; by which, their internal organs
are sheltered. In some which always droop, as the
Snowdrops Galanthus and Leucgjum, Engl. Bot. t.19
and 621, the Fritillary, ¢. 622, the Crown Imperial,
various species of Campanula, and others, while: the
overshadowing corolla keeps off rain, the air has free
access underneath to blow the pollen to the stigma.
Nor is this drooping caused by the weight of the
flowers, for the fruit in most of them is much heavier,
and yet stands erect on the very same stalk. The pa-
pilionaceous flowers in general spread their wings in ~
fine weather, admitting the sun and air to the parts
within; whereas many of them not only close their
petals at night, but also derive additional protection

EXPERIMENTS ON HEMP. 251

from the green leaves of the plant folding closely about
-them. Convoloulus arvensis, t.312, Anagallis ar-
wensis, t. 529, Calendula pluvialis, and many others,
are well known to shut up their flowers against the
approach of rain; whence the Anagallis has been
called the Poor Man’s Weather-glass. It has been
observed by Linnzus that flowers lose this fine sen-
sibility, either after the anthers have performed their
office, or when deprived of them artificially; nor do-
I doubt the fact. I have had reason to think that,
during a long continuance of wet, the sensibility of
the Anagallis is sometimes exhausted ; and it is evi-
dent that very sudden thunder-showers often take
such flowers by surprise, the previous state of the at-
mosphere not having been such as to give them due
warning. |

That parts of vegetables not only lose their irrita-
bility, but even their vital principle, in consequence of
having accomplished the ends of their being, appears
from an experiment of Linnzus upon Hemp. This
is a dicecious plant, see p. 234, and Linneus kept
several fertile-flowered individuals in separate apart-
ments from the barren ones, in order to try whether
they could perfect their seeds without the aid of pol-
len. Some few however remained with the barren-
flowered plants, and these ripened seed in due time,
their stigmas having faded and withered soon after
they had received the pollen. On the contrary, the
stigmas which had been out of its reach continued

252 EXPERIMENTS ON MELONS, CYCAS, ETC.

green and vigorous, nor did they begin to fade till
they had thus lasted for a very long while. Since
I read the history of this experiment, I have found —
it easy in many plants to tell by the appearance
of the stigma whether the seed be fertilized or not.
The above experiment is the more important, as the
abbé Spallanzani has recorded one made by himself
upon the same species of plant, with a contrary
result. But as he has said nothing of the appearance
of the stigmas, his experiment inust yield to that of
Linnzus in point of accuracy ; and even if his ac-
count be otherwise correct, the result is easily ex-
plained. Hemp, Spinach, some Nettles, &c., na-
turally dicecious, are occasionally not completely so,
a few latent barren or fertile flowers being frequently
found among those of the other sort, by which pro-
vision is made against accidents, and the perfecting of
a few seeds, at any rate, secured.

In general, germens whose stigmas have not received
the pollen wither away without swelling at all ; but
some grow to a considerable size, and in such the sub-
stance of the seed, its skin, and even its cotyledons,
are often to be found, the embryo only being wanting.
Ina Melon or Cucumber it is common to find, among
numerous perfect seeds, many mere unimpregnated
husks. In the magnificent Cycas revoluta which bore
fruit at the bishop of Winchester’s, and of which a
history with plates is given in the sixth volume of the
Linnaan Society’s Transactions, I found the drupa

(CONOMY OF AQUATIC PLANTS. 953

- and all its contents: apparently perfect, except that
there was only a minute cavity where the embryo
should have been, in consequence of ‘the want of) an-
other’ tree with stamens; which was not to be found
perhaps nearer than Japan. Gardeners formerly at-
tempted to assist Nature by stripping off the barren
flowers of Melons and Cucumbers, which, having no
germeén, they found could not come to fruit, and were
_theréfore,'as they supposed, an unnecessary encum-
brance tothe constitution of the parent plant. But
finding ‘that, by such a’ practice, they obtained» no
fruit at all, they soon learned the wiser method of
admitting air‘as often as possible to the flowering
plants, for the purpose of blowing the pollen from one
blossom to ‘the other, and even to gather the barren
kind, and'place it over that destined to bear fruit.
The ceconomy of’ various aquatic plants’ throws
great light upon the subject before us. Different spe-
cies of Potamogeton, Engl. Bot. t. 168, 297, 376,
&e., Ruppia maritima, t. 136, and others, float en-
tirely under water, often at some considerable depth,
till the flowering season arrives, when they rise near
the'surface, and throw up their flowering spikes above
it, sinking afterwards to ripen“and sow their seeds at
the bottom.» Wymphea alba, t. 160, is very truly de-
scribed ‘by Linneus in-his Mora Suecica, as closing
its flowers in the afternoon and laying them down
upon the surface of the water till morning, when it

954 OF THE NYMPHEA.

raises and expands them, often, in a bright day, to
several inches above the water. ‘To this I can speak
from my own knowledge, and it is confirmed by the
history given by Theophrastus of his Zotus, which,
according to all appearance, is the Nymphea Lotus of
Linneus. “This,” says he, ‘as well as the Cyamus*,
bears its fruit in a head. The flower is white, consist-
ing of many crowded leaves about as broad as those of
alily. These leaves at sunset fold themselves together,
covering the head (or seed-vessel). At sun-rise they
expand, and rise above the water. This they continue
till the head is perfected, and the flowers fall off.” So
far Theophrastus writes as of his own knowledge ; he
continues as follows: “ It is reported that in the Eu-
phrates the head and flowers keep sinking till mid-
night, when they are so deep in the water as to be
out of reach of the hand, but towards morning they
return, and still more as the day advances. At sun-
rise they are already above the surface, with the flower
expanded ; afterwards they rise high above the water.”
Pliny repeats the same account ; and Prosper Alpinus, »
whose purpose is to prove the Lotus of ‘Theophrastus
not different from the common Nymphea, in which,
as far as genus is concerned, he is correct, has the fol-
lowing remarkable passage: ‘‘ The celebrated stories
of the Lotus turning to the sun, closing its flowers.

* Exot. Bot. t. $1, 32.

OF THE VALISNERIA. 255

and sinking under water at night, and rising again in
the morning, are conformable to what every body has
observed in the Nymphea.”

I have been the more particular in the above quota-
tions, because the veracity of ‘Theophrastus has lately
been somewhat rudely impeached, on very question-
able authority. For my own part, I think what we

_ see of the Nymphea in England is sufficient to render

the above account highly probable in a country where
the sun has so much more power, even if it did not
come from the most faithful and philosophical bota-
nist of antiquity, and I have always with confidence
cited it on his authority. ‘The reader, however, will
perceive that the only important circumstance for our
purpose is the closing of the flowers at night, which is
sufficiently well established.

But the most memorable of aquatic plants is the
Valisneria spiralis, well figared and described by
Micheli, Nov. Gen. ¢. 10, which grows at the bottoms
of ditches in Italy. In this the fertile flowers stand on —
long spiral stalks, and these by uncoiling elevate them
to the surface of the water, where the calyx expands —
in the open air. In the mean while plenty of barren
flowers are produced on adistinct root, on short straight
stalks, from which they rise like little separate white
bubbles, suddenly expanding when they reach the
surface, and floating about in such abundance as to
cover it entirely. Thus their pollen is scattered over
the stigmas of the first-mentioned blossoms, whose

956 ASSISTANCE OF INSECTS IN IMPREGNATION.

stalks soon afterwards resume their spiral figure, and.
the fruit comes to maturity at the bottom of the water.

All this Micheli has described, without being aware

of its final purpose; so different is it to observe and
to reason !

Some aquatic vegetables, which blossom anal
water, seem to have a peculiar kind of glutinous pol-
len, destined to perform its office in that situation, as
Chara, Engl. Bot. t. 336, &c.; as well as the Fucus
and Conferva tribe; but of the real nature of the fruc-
tification of these last we can at present only form
analogical conjectures. |

The fertilization. of the Fig is accomplished in a -

striking manner by insects, asis that of the real Syca-
more, Iicus Sycomorus. In this genus the green fruit
is a hollow common calyx, or rather receptacle, lined
with various flowers, seldom both barren and fertile
in the same fig. This receptacle has only a very small
orifice at the summit. The seeds therefore would not
in general be perfected, were it not for certain minute
flies of the genus Cynips, continually fluttering from
one fig to the other all covered with pollen, and depo-
siting their eggs within the cavity.

-

A.very curious observation is recorded by Ca laaaliiil ‘

and Willdenow concerning the Aristolochia Clematitis,
Engl. Bot. t. 398. The stamens and pistils of, this
flower are inclosed in its globular base, the anthers
being under the stigma, and by no means commodious-
ly situated for conveying their pollen to it.. This there-

ASSISTANCE OF INSECTS IN IMPREGNATION. 257

fore is accomplished by an insect, the 77pedla penne-
cornis, which enters the flower by the tubular part.
But that part being thickly lined with yflexed hairs,
though the fly enters easily, its return is totally im-
peded, till the corolla fades, when the hairs he flat
against the sides, and allow the captive to escape. In
the mean while the insect, continually struggling for
liberty, and pacing his prison round and round, has
brushed the pollen about the stigma. Ido not doubt
the accuracy of this account, though-I have never
caught the imprisoned Zipula*. Indeed I have never
seen any fruit formed by this plant. Probably for want
of some insect adapted to the same purpose In its own
country, the American Aristolochia Sipho, though it
flowers plentifully, rarely forms fruit in our gardens.
That it sometimes does, I have been informed by the
late Lady Amelia Huine, since the first edition of this
work was published. |

The ways in which insects serve the same purpose -
are innuinerable. ‘These active little beings are pecu-
liarly busy about flowers in bright sunny weather, when
every blossom is expanded, the pollen in perfection,
and all the powers of vegetation in their greatest vigour.
Then we see the rough sides and legs of the bee, laden
with the golden dust, which it shakes off, and collects
anew, in its visits to the honeyed stores inviting it on

| ‘

* Dr. Lamb of N ewbury has lately sent me specimens of the flowers,
with the insict inclosed, from the Oxford garden, where they were
_ discovered by a young gardener.— August 1815.

i)

958 ASSISTANCE OF INSECTS IN IMPREGNATION.

a

every side. All nature is then alive, and a thousand
wise ends are accomplished by innumerable means
that ‘seeing we perceive not;” for though in the
abundance of creation there seems to be a waste, yet
in proportion as we understand the subject, we find
the more reason to conclude that nothing is made in
vain.

CHAPTER, XXL

ON THE DISEASES OF PLANTS, PARTICULARLY AS
ILLUSTRATIVE OF THEIR VITAL PRINCIPLE.

Tur diseases of Vegetables serve in many instances.
to prove their vitality, and to illustrate the nature of
their constitution.

Plants are subject to Gangrene or Sphacelus, espe-
cially the more succulent kinds, of which a very
curious account, concerning the Cactus coccinellifer,
Indian Fig, or Nopal, extremely to our present pur-
pose, is given by M. Thiery de Menonville, in his
work on the culture of the Nopal as the food of the
_ Cochineal insect. This writer travelled about 30 years

since, through the Spanish settlements in South Ame-
rica, chiefly noted for the cultivation of this precious
insect, on purpose to transport it clandestinely to some
of the Trench islands. Such were the supineness and
ignorance of the Spaniards, that he succeeded in con-
veying, not only the living insects, but the bulky plant
necessary for their sustenance, notwithstanding severe
edicts to the contrary. He had attended previously to
the management of the Nopal, and made his remarks
on the diseases to which it is liable. Of these the
Gangrene is extremely frequent in the true Nopal of
Mexico, beginning by a black spot, which spreads till
SQ

260 GANGRENE OF PLANTS.

the whole leaf or branch rots off, or the shrub dies.
But the same kind of plant is often affected witha —
much more serious disease, called by Thiery “ la disso-
lution.” ‘This seems to be a sudden decay of the vital —
principle, like that produced in animals by lightning |
or strong electricity. In an hour’s time, from some
unknown cause, a joint, a whole branch, or sometimes
an entire plant of the Nopal, changes from apparent _
health to a state of putrefaction or dissolution. One
minute its surface is verdant and shining; the next it
turns yellow, and all its brilliancy is gone. On cutting
into its substance, the inside is found to have lost all
cohesion, being quite rotten. ‘The only remedy in this
case is speedy amputation below the diseased part.
Sometimes the force of the vital principle makes a
stand, as it were, against the encroaching disease, and
throws off the infected joint or branch. Such is the
account given by Thiery, which evinces a power in
vegetables precisely adequate to that of the animal
constitution, by which an injured or diseased part is,
by an effort of Nature, thrown off to preserve the rest.
Nor need we travel to Mexico to find examples of
this. Every deciduous tree or shrub exhibits the very
same phenomenon; for the fall of their decaying
foliage in autumn, leaving the branches and young
buds vigorous and healthy, can be explained in no
other way. Yet Du Hamel laboured in vain to account
for the fall of the leaf* ; nor is it wonderful that he or

* See his Phys. des Arbres, 0. 1. 127.

FALL OF THE LEAF. | 261

any body else, who endeavours to explain the physio-
logy of vegetables or of animals according to one prin-
ciple only, whether it be mechanical or chemical,
should entirely fail. To consider the fall of leaves in
autumn as a sloughing, or casting off diseased or worn
out parts, seems so simple and evident, as to be hardly
worth insisting upon. Yet I find myself anticipated in
this theory by one physiologist only, named Vrolick,
cited by Willdenow, in his Principles of Botany,
p- 304, though several learned speculations to no pur-
pose are extant on the subject. Itis but just, however,
that I should relate what led me to consider the matter
with any attention. My observing friend Mr. Fairbairn
of Chelsea garden long ago remarked to me, that when
he had occasion to transplant any tree or shrub whilst
in leaf, he could soon judge of its success by the ease
with which its leaves were detached. The consequence
of such treatment is more or less injury to the health
of the plant, as will. first appear by the drooping of
the leaves, most of which will probably die, and the
decay will generally be extended to the younger more
delicate twigs. The exact progress of this decay may
speedily be known, by the leaves of those branches
which are irrecoverably dying or dead, remaining
firmly attached, so as not to be pulled off without a
force sufficient to bring away the bark or buds along
with them: whereas the leaves of parts that have re-
ceived no material injury, and where the vital energy
acts with due power, either fall off spontaneously or

962 FALL OF RIPE FRUIT.

are detached by the slightest touch. Plants of hot
countries, kept in our stoves, exhibit the same pheno-
menon when transplanted or otherwise injured, even
though not naturally deciduous.

So when fruits are thoroughly ripened, they become,
with respect to the parent plant, dead substances, and,
however strongly attached before, are then thrown off
as extraneous bodies. Their stalks fade or wither,
though the life of the adjoining branch continues un- .
impaired, anda line of separation is soon drawn. Ina
poor soil, or unfavourable climate, a bunch or spike
which should naturally consist of a considerable number
of flowers, bears perhaps not half so many. Its upper
part very early withers, the vital principle ceases to act
at the point beyond which it could not continue to act
with effect, and all its energy is directed to perfect
what lies within the compass of its resources. ‘This is
evident in Lathyrus odoratus, the Sweet Pea of our
gardens, a native of a very hot climate, at the summits
of whose flower-stalks are generally found the rudi-
ments of one or more flowers, not attempted to be
perfected. So also the first Barley sown on the sandy
heaths of Norfolk, and indeed too many a following
crop, bears very few grains in an ear; for the same ©
meagre supply of nourishment, bestowed equally on a
numerous spike of blossoms, would infallibly starve
them all. In like manner one sced only is perfected in
the best wild Arabian Coffee, known by its round
form; while the West Indian plantation Coffee has

\

OF GALLS AND VARIOUS EXCRESCENCES. 263

two in each berry, both consequently flattened on one

side. ‘The former grows in barren open places, in

situations sufficiently favourable for the impregnation
of its blossoms, but far less so for the perfecting of
much seed ; while the latter, well supplied with manure
and moisture, is enabled to bring every germ to ma-
turity.

Very strange effects are often produced upon plants
by the attacks of insects, whence the various kinds of
Galls derive their origin. ‘These are occasioned by the
punctures of those little animals, chiefly of the Zymen-
optera order, and of the genus Cyzps, in some vigo-
rous part of the plant, as the leaves, leaf-stalks, young
stem or branches, and sometimes the calyx or germen.
The parent insect deposits its egg there, which is soon
hatched; and in consequence of the perpetual irritation
occasioned by the young maggot, feeding on the juices.
of the plant, the part where it is lodged acquires a
morbid degree of luxuriance, frequently swelling to an
immoderate size, and assuming the most extraordinary
and whimsical shapes. ‘This often happens to the
shrubby species of Hawkweed, Hieracium sabaudum,
Lingl. Bot. t. 349, and umbellatum, t. 1771, whose .
stems in consequence sweil into oval knots. Several

_ different kinds of Gal!s are borne by the Oak, as ‘these

light spongy bodies, as big as walnuts, vulgarly named
Oak apples; a red juicy berry-like excrescence on its
leaves ; and the very astringent Galls brought from the
Levant, for the purposes of ‘dyeing and making ink,

~

264 REMARKABLE EXCRESCENCES.

which last are produced by a different species of
Quercus from either of our own. The common Dog-
rose, ¢. 992, frequently bears large moss-like balls, in
whose internal parts numerous maggots are always to
be found, till they become the winged Cynips Nose,
and eat their way out. Many of our Willows bear
round excrescences, as large as peas, on their leaves;
but I remember to have been very much astonished in
Provence with a fine branched production on the W3l-
lows in winter, which appeared like a tufted Lichen,
but proved on examination a real Gall. Indeed our
Salix Helix, t. 1343, is called Rose Willow from its
bearing no less remarkable an excrescence, like a rose,
at the ends of some of its branches, in consequence of
the puncture of an insect; and these are in like manner
durable, though the proper leaves fall. The Mastic-.
tree, Pistacia Lentiscus, is often laden, in the south
of Europe, with large red hollow finger-like bodies,
swarming internally with small insects, the Aphis
Pistacie of Linneus. The young shoots of Salvia
pomifera, Fl, Grec. t. 15, 8. triloba, t, 17, and even
S. officinalis, in consequence of the.attacks probably
of some Cynips, swell into large juicy balls, very like
apples, and even crowned with rudiments of leaves
resembling the calyx of that fruit. These are esteemed
in the Levant for their aromatic and acid flavour , espe-
cially when prepared with sugar.

It may be remarked that all the excrescences above
mentioned are generally more acid than the rest of the

DISEASES OF THE SKIN. 265

plant that bears them, and also greatly inclined to turn
red. Theacid they contain is partly acetous, but more
of the astringent kind. |

The diseases of the skin, to which many vegetables
are subject, are less easily understood than the forego-
ing. Besides one kind of Honey-dew, already inen-
tioned, p. 144, something like leprosy may be ob-
served in Zragopogon major, Jacq. Austr. t. 29,
which, as I have been informed by an accurate ob-
server, does not injure the seed, nor infect the progeny.
The stem of Shepherd's Purse, Hngl. Bot. t. 1485, is
occasionally swelled, and a white cream-like crust,
alterwards powdery, ensues. The White Garden
Rose, Rosa alba, produces, in like manner, an orange-
coloured powder. It proves very difficult, in many
cases, to judge whether such appearances proceed from
a primary disease in the plant, arising from unseason-
able cold or wet, or are owing to the baneful stimulus
of parasitical fung? irritating the vital principle, like
the young progeny of insects as above related. Sir
Joseph Banks has, with great care and sagacity, traced
the progress of the Blight in Corn, Uredo frumenti,
Sowerd. Fung. t. 140, and given a complete history
of the minute fungus which causes that appearance.
See Annals of Botany, v. 2. 51,.t. 3, 4. Under the
inspection of this eminent promoter of science, Mr.
Francis Bauer has made microscopical drawings of
many similar fungi infecting the herbage and seeds’ of
several plants, but has decided that the black swelling

266 OF THE BLIGHT, ETC.

of the seed of corn, called by the French Ergot, though
not well distinguished from other appearances by the
generality of our agricultural writers, is indubitably a
morbid swelling of the seed, and not in any way con-
nected with the growth of a fungus. The anthers of
certain plants often exhibit a similar disease, swelling,
and producing an inordinate quantity of dark purplish
powder instead of true pollen, as happens in Silene
inflata, Fl. Brit. Engl. Bot. t. 164, and the white
Lychnis dioica, t. 1580, whose petals are, not uncom-
monly, stained all over with this powder. Our know-
ledge on all these subjects is yet in its infancy ; but it
is to be hoped, now the pursuit of agriculture and of

philosophical botany begin to be, in some distinguished

instances, united, such examples will be followed, and
science directed, to one of its best ends, that of im-
proving useful arts. And here I cannot but mention
the experiments continually going on under the inspec-

-

tion of the ingenious Mr. Knight, of fertilizing the

germen of one species or variety with the pollen of
another nearly akin, asin apples, garden peas, &c., by
which, judiciously managed, the advantages of different
kinds are combined. By the same means Linnzus

obtained intermediate species or varieties of several -

plants; and if anything were wanting to confirm his
theory respecting the stamens and pistils, this alone
would place it out of all uncertainty.

/

tS)
>)
N

CHAPTER XXII.

=

OF THE SYSTEMATICAL ARRANGEMENT OF PLANTS.

NATURAL AND ARTIFICIAL METHODS. GENERA,
SPECIES, AND VARIETIES. NOMENCLATURE.

Ture foregoing chapters have sufficiently explained
the parts of plants, and the leading differences in their
conformation; for us now to proceed to the Systema-
tical part of our subject. In this, when properly un-
derstood and studied, there is no less exercise for the
inind, no less employment for its observation and ad-

_miration, than in physiological or anatomical inquiries ;

nor are the organs of vegetables, when considered only
as instruments of classification and discrimination, less
conspicuous for beauty, fitness, and infinite variety of
contrivance, than under any other point of view. ‘The
wisdomof an Infinite Superintending Mind isdisplayed
throughout Nature, in whatever way we conteinplate
her productions. ;
Vhen we take into consideration the multitude of

species which compose the vegetable kingdom, even in

any one country or climate, it is obvious that some
arrangement, some regular mode of naming and di-

_ stinguishing them, must be very desirable, and even

necessary, for retaining them in our own memory, or
for communicating to others any thing concerning

968 OF BOTANICAL ARRANGEMENT.

them. Yet the ancients have scarcely used any further |

classification of plants than the vague and superficial
division into trees, shrubs and herbs, except a conside-

ration of their places of growth, and also of their

qualities. The earlier botanists among the moderns
almost inevitably fell into some rude arrangement of
the objects of their study, and distributed them under
the heads of Grasses, Bulbous plants, Medicinal or
Eatable plants, &c., in which. their successors made
several improvements, but it is not worth while to con-
template them.

The science of Botanical i rangement first assumed
a regular form under the auspices of Conrad Gesner

and Cesalpinus, who, independent of each other, with-

out any mutual communication, both conceived the

idea of a regular classification of plants, by means of

the parts of fructification alone, to which the very ex-

istence of Botany as a science 1S owing. ‘The first of

these has left us scattered hints only, in various letters,
communicated to the world after his premature death
in 1565: the latter published a system, founded on

the fruit, except the primary division into trees and |

herbs, in a quarto volume printed at Florence in 1583.
This work Linneus studied with great care, as appears
from the many notes and marked passages in his own
copy now before me. Hence he adopted his ideas of
the supposed origin of the calyx, corolla, stamens, and

pistils, from the outer bark, inner bark, wood and pith,

which are now proved to be erroneous. In his. own

~

~

METHODS OF CESALPINUS, RIVINUS, ETC, 269

Classes Plantarum he has drawn out a regular plan of
the System of Czesalpinus, the chief principles of which
are the following ;

1. Whether the embryo be at the sumrait or base of
the seed. wr)

2. Whether the germen be superior or inferior.

3. Seeds 1, 2, 3, 4, or numerous.

4. Seed-vessels 1, 2, 3, 4, &c.

The work of Cesalpinus, though full of informa-
tion, was too deep to be of common use, and excited
but little attention. A century afterwards Morison, |
Professor of Botany at Oxford, improved somewhat
upon the ideas of the last-mentioned writer, but has
been justly blamed for passing over in silence the
source of his own information. Ray, the great [n-
glish naturalist, formed a considerably different system
upon the fruit, as did Hermann, Professor at Leyden,
and the great Boerhaave ; but in these last there is
little originality. |

Rivinus, Ruppius and Ludwig in Germany proposed
to arrange plants by the various forms of their Corolla,
as did Tournefort the illustrious French botanist, whose
system is by far the best of the kind; and this having
been more celebrated than most others, I shail givea
sketch of its plan. |

In the first place we meet with the old but highly
unphilosophical division into Herbs and ‘Trees, each of

270 METHODS OF TOURNEFORT AND MAGNOL.

which sections is subdivided into those with a Corolla
and those without. The Trees with a Corolla are
again distributed into such as have one or many petals,
and those regular or irregular.—Herbs with a Corolla
have that part either compound (as the Dandelion,.
Thistle and Daisy), or simple; the latter being either
of one or many petals, and in either case regular or
irregular. We come at last to the final sections, or
classes, of the Tournefortian system. Herbs with a
simple, monopetalous, regular corolla are either bell-
shaped or funnel-shaped ; those with an irregular one
either anomalous or labiate. erbs with a simple;.
polypetalous, regular corolla are either cruciform, ro-
saceous, umbellate, pink-like or liliaceous; those with
an irregular one, papilionaceous or anomalous. The
subdivisions of the classes are founded on the fruit. .

It is easy to perceive that a system of this kind can
never provide for all the forms of corolla which may
be discovered after its first contrivance ; and there-
fore the celebrated Dr. Garden, who studied by it, as-
sured me, that when he attempted to reduce the Ame-
rican plants to Tournefort’s classes, he found themso |
untractable, that, after attempting in vain to correct
or augment the system, he should probably have given
up the science in despair, had not the works of Lin- |
nus fallen in his way.

Magnol, Professor at Montpellier, and even Linnzeus —
himself, formed schemes of arranging plants by the
calyx, which nobody has followed.

OF A NATURAL MODE OF CLASSIFICATION. 271

All preceding systems, and all controversies respect-
ing their superior merits, were laid aside, as soon as the
famous Linnean method of classification, founded on
the Stamens and Pistils, became known in the botanical
world. Linnzus, after proving these organs to be the
most essential of all to the very being of a plant, first
conceived the fortunate idea of rendering them subser-
vient to the purposes of methodical arrangement, taking
into consideration their number, situation and propor-
tion. How these principles are applied, we shall pre-
sently explain; but some previous observations -are
- necessary.

Linneus first made a distinction between a natural
and an artificial method of botanical arrangement.
His predecessors probably conceived their own systems
to be each most consonant with the order of Nature,
as well as most commodious for use, and it was re-
served for him to perceive and to explain that these
were two very distinct things.

The most superficial observer must perceive some-.
thing of the classification of Nature. The Grasses,
Umbelliferous plants, Mosses, Sea-weeds, Ferns, Lilia-
ceous plants, Orchises, Compound flowers, each con-
stitute a family strikingly similar in form and qualities
among themselves, and no less evidently distinct from
all others. If the whole vegetable kingdom could with
equal facility be distributed into tribes or ciasses, the
study of Botany on sucha plan would be no less easy

2972 OF A NATURAL MODE OF CLASSIFICATION.

than satisfactory. But as we proceed in this path, we
soon find ourselves in a labyrinth. The natural orders
and families of plants, so far from being connected ina
regular series, approach one another by so many points,
as to bewilder instead of directing us. We may seize
some striking combinations and analogies ; but the
further we proceed, the more we become sensible that,
even if we had the whole vegetable world before us at
one view, our knowledge must be imperfect, and that
our “ genius” is certainly not “ equal to the Majesty
of Nature.” Nevertheless Linneus, and all true phi-
losophical botanists, since the first mention of the na-
tural affinities of plants, have ever considered them as
the most important and interesting branch, or rather |
the fundamental part, of systematical botany. With-—
out them the science is truly a study of words, con-
tributing nothing to enlarge, little worthy to exercise,
arational mind. Linneeus therefore suggests a scheme
which he modestly calls Fragments of a Natural
Method, which formed the subject of his occasional
contemplation ; but he daily and hourly studied the
principles of natural affinities among plants, conscicus
that no true knowledge of their distinctions, any more
than of their qualities, could be obtained without; of —
which important truth he was not only the earliest,
but ever the most strenuous assertor. . ra

In the mean while, however, Linnzeus, well aware
that a natural classification was scarcely ever to be

LINNZEAN ARTIFICIAL METHOD. 273

completely discovered, and that if discovered it would
probably be too difficult for common use, contrived an
artificial system, by which plants might conveniently
be arranged, like words in a dictionary, so as to be
most readily found. If all the words of a language
could be disposed according to their abstract deriva-
tions, or grammatical affinities, such a performance
might be very instructive to a philosopher, but would
prove of little service to a young scholar; nor has it
ever been mentioned as any objection to the use of a
dictionary, that words of very different meanings, if
formed of nearly the same letters, often stand toge-
ther. The Method of Linneus therefore is just such
a dictionary in Botany, while his PAzlosophia Botanica
is the grammar, and his other works contain the
history, and even the poetry, of the science.

But before we give a detail of his artificial system,
we must first see how this great man fixed the funda-
mental principles ef botanical science. Nor are these
principles confined to botany, though they originated
in that study. The Linnean style of discriminating
plants, has been extended by himself and others to
animals and even fossiis ; and his admirable principles -
of nomenclature are applied with great advantage even
to chemistry itself, now become so vast and accurate
a science.

Independently of all general methods of classifica-

_tion, whether natural or artificial, plants, as well as
’ T

274 OF GENERA AND

animals, are distinguished into Genera™, Species, and
Varieties. Bi, &

By Species are understood so many individuals, or,
among the generality of animals, so many pairs, as
are presumed to have been formed at the creation, and
have been perpetuated ever since; for though some
animals appear to have been exterminated, we have
no reason to suspect any new species has been pro-
duced ; neither have we any cause to suppose any
species of plant has been lost, nor any new one per-

manently established, since their first formation, not-

withstanding the speculations of ‘some philosophers.
We frequently indeed see new Varieties, by which
word is understood a variation in an established spe-
cies ; but such are imperfectly, or for a limited time,
if at all, perpetuated in the offspring. 3

A Genus comprehends one or more species, $0 es-

sentially different in formation, nature, and often many
adventitious qualities, from other plants, as to consti-
tute a distinct family or kind, no less permanent, and
founded in the immutable laws of the creation, than
the different species of such a genus. ‘Thus in the
animal kingdom, a horse, ass and zebra form three
species of a very distinct genus, marked, not only by

7

* Our scientific language in English is not sufficiently perfect to

afford a plural for genus, and we are therefore obliged to adopt the Latin
one, genera, though it exposes us sometimes to the horrors of hearing
of “ a new genera” of plants. i

rx
ee nee

THEIR CHARACTERS. 975

its general habit or aspect, its uses and qualities, but
also by essential characters in its teeth, hoofs, and in-
ternal constitution. The lion, tiger, leopard, panther,
lynx, cat, &c., also compose another sufficiently ob-
vious and natural genus, and the numerous herd of
monkeys, apes and baboons a third. The hippopo-
tamus is, as far as we know, <a solitary species of a
most distinct and striking genus ; and the elephant
has, till lately, been thought to stand alone in another.

So among vegetables, the various species of rose

compose a beautiful genus, known to every one who
ever looked at a plant, merely by a certain combina-
tion of ideas, but essentially distinguished, as we shall
hereafter find, by clear and decisive characters. The
species of {vis form also a numerous genus, and the
Wiilows another; while the curious Epimedium al--
pinum, Engl. Bot. t.438, is too singular and distinct
to be associated with any known plant besides, and
constitutes a genus by itself, as well as the Adova,
t.453, and Linnea, t. 435.

The first great and successful attempt to define the
genera of plants was made by Tournefort, and in this
his transcendent merit will ever be conspicuous, though
his system of arrangement should be entirely forgotten.

Not that he has excelled in verbal definitions, nor built
all his genera on sure foundations; but his figures,
and his enumerations of species under each genus,
show the clearness of his conceptions, and rank him
as the father of this branch of botany.

TS

276 CHARACTERS

Linneus first insisted on generic characters being
exclusively taken from the seven parts of fructification,
and he demonstrated these to be sufficient for all the
plants that can be discovered. He also laid it down
as a maxim, that all genera are.as much founded in
nature as the species which compose them ; and hence
follows one of the most just and valuabie of all his
principles, that @ genus should furnish a character,
not a character forma genus; or, in other words,
that a certain coincidence of structure, habit, and per-
haps qualities, among a number of plants, should
strike the judgement of a botanist, before he fixes on
one or more technical characters, by which to stamp
and define such plants as one natural genus. ‘Thus
the Hemerocallis cerulea, Andr. Repos. t. 6, and

alba, t. 194, though hitherto referred by all botanists
to that genus, are so very different from the other
species in habit, that a discriminative character might
with confidence be expected in some part or other of ©
their fructification, and sucha character is accordingly
found in the winged seeds. Yet in the natural genera
of Arenaria and Spergula, winged or bordered seeds
are so far from indicating a distinct genus, that it is
doubtful whether they are sufficient to constitute even
a specific character. See Engl. Bot. t. 958, 1535
and 1536. So Blandfordia, Exot. Bot. t. 4, is well
distinguished from Aletris, with which some botanists
have confounded it, by its hairy seeds ; but the same
circumstance will not justify us in separating a few

OF GENERA. 277

species from Convoloulus, which are attached to that
genus by stronger ties of another kind.

Some genera are obvious and indubitable both in
habit and character, as Quercus, Rosa, Euphorbia,
Begonia, Exot. Bot. t. 101, and Sarracenia, t. 53 ;
others are obvious, but their character extremely dif-
ficult to define, as Valeriana. ‘The greatest difficulty
lies in distinguishing genera that belong to such very
natural orders as the Grasses and Umbelliferous
plants ; and the ablest botanists differ about the best
guides in these two particular cases. Yet other orders,
equally natural, sometimes afford very excellent ge-
neric differences, as that to which Rosa, Rubus, Fra-
garia, &c., belong; and even in the Papilionaceous.
plants with ten distinct stamens, a tribe hitherto judged:
inextricable, a regular examination on scientific prin-
ciples has led to the discovery of very natural well de-
fined genera. See Annals of Botany, v.1.501. 1
have in a preceding chapter hinted that the -umbelli-
ferous plants seem to me very capable of being well
discriminated by their seeds, and other botanists have
held the same opinion. |

But though I feel convinced, as far as my experience
goes, that genera are really founded in nature, I am
far from asserting that Linnzus, or any other writer,
has succeeded in fixing all their just limits. This deep
and important branch of natural scienee requires the
union of various talents. Many persons who can per-
ceive a genus cannot define it ;. nor do acuteness of

978 CHARACTERS OF GENERA.

perception, solidity of judgement, and perspicuity of
expression, always meet in the same person. Those
who excel in this department are named by Linneus,
’ Phil. Bot. sect. 152, theoretical botanists; those who
study only species and varieties, practical ones.

In methodical arrangement, whether natural or arti-
ficial, every thing must give way to generic distinc-
tions. A natural system which should separate the
species of a good genus, would, by that very test
alone, prove entirely worthless ; and if such a defect
be sometimes unavoidable in an artificial one, con-
trivances must be adopted to remedy it; of which
Linneus has set us the example, as will hereafter be
explained.

Generic characters are reckoned by Buel of three
kinds, the factitious, the essential, and the natural, all
founded on the fructification alone, and not-on the
inflorescence, nor any other part.

The first of these serves only to discriminate genera
that happen to come together in the same artificial
order or section; the second, to distinguish a particular
genus, by one striking mark, from all of the same
natural order, and consequently from all other plants;
and the third comprehends. every possible mark com-
mon to all-the species of one genus: !

The factitious character can never stand alas but
may sometimes, commodiously enough, be added to
more essential distinctions, as the insertion of the
petals in Agrimonia, Engl. Bot. ¢. 1335, indicating

OF ESSENTIAL GENERIC CHARACTERS. 279

the natural order to which the plant belongs, which
character, though essential to that order, here becomes
factitious.

Linnzus very much altered his notions of the essential
character after he had published his Philosophia Bo-
tanica, whence the above definitions are taken. In-
stead of confining it to one mark or idea, he, in his
Systema Vegetabilium, makes it comprehend all the
distinctions requisite to discriminate each genus from
every other in the system, only avoiding a repetition
at every step of the characters of the artificial class
and order, which stand at the top of each page, and
are not always essential to the character of the genus.
This is the kind of generic character now universally
adopted, and indeed the only one in common use.
The learned Jussieu has given it the sanction of his
approbation and adoption, as far as its plan is con-
cerned, throughout his immortal work, subjoining in
a different type such characters and remarks as belong
to the habit, or refer to other circumstances. For my
own part I profess to retain, not only the plan, but
the very words of Linneus, unless I find them erro-
neous, copying nothing without examination, but alter-
ing with a very sparing hand, and leaving much for fu-
ture examination. I cannot blame my predecessors
for implicitly copying the Linnean characters, nor
should I have been the first among English writers to
set a contrary example, had I not fortunately been fur-
nished with peculiar materials-for the purpose.

280 CONSTRUCTION OF

The beauty and perfection of these essential generic
characters consist in perspicuity, and a clear concise
style of contrasting them with each other. All feeble-
ness, all superfluity, should be avoided by those who
are competent to the purpose, and those who are not
should decline the task. Comparative words, as long
or short, without any scale of comparison, are among
the grossest, though most common, faults in such com-
positions. : |

The natural character seems to have been, at one
time, what Linneus most esteemed. It is what he
has used throughout his Genera Plantarum, a work
now superseded by the essential characters in his
Systema Vegetabilium, and therefore in some measure
laid aside. The disadvantages of the natural character
are, that it does not particularly express, nor direct
the mind to, the most important marks, and that it
can accord only with such species of the genus as are
known to the author, being therefore necessarily im-
perfect. This kind of character is, however, admi-
rable for the illustration of any difficult natural order.
Mr. Gawler’s elucidations of the Hnsata, Sword-
leaved plants, Annals of Botany, v. 1.219, and Curt.
Mag. afford excellent specimens of it, serving as a
store of facts and observations for following systema-
tical writers.

Specific characters should be constructed on similar
principles to the generic ones, as far as regards cer-
tainty, clearness and conciseness, ‘The genus being

SPECIFIC CHARACTERS. 238i

first well defined, we are to seek for characters, not
mentioned among the generic marks, for distinguishing
the species. A specific difference for a solitary species
of any genus, 1s therefore an absurdity. Linneus at
first intended his specific definitions should be used as
names; but the invention of trivial names happily set
aside this inconvenient scheme. On this account how-
ever he limited each to twelve words, a rule to which
all philosophical naturalists have adhered, except in
cases of great necessity. Nor is the admission of one
or two words beyond the allotted number reprehensible,
provided the whole sentence be so neatly and perspi-
cuously constructed, that the mind may comprehend
it, and compare it with others, at one view ; but this
can hardly be done when the words much exceed
twelve. This rule, of course, can be strictly applied
to Latin definitions only, though it should be kept in
view in any language, as far as the genius of that lan-
guage will allow. Linnzus says, ‘‘ Genuine specific di-
stinctions constitute the perfection of natural science ;”
which is strongly confirmed by the great inferiority of
most botanists, in this department, to that great man,
and especially by the tedious feebleness and insufhi-
ciency, displayed among those who court celebrity by
despising his principles.

In constructing generic and specific characters, the
arrangement of the different parts on which they are
founded is to be considered. Such as are most impor-
tant in the natural order, or genus, are to stand first,

982 PRINCIPLES

and the subordinate, or more peculiar marks of the
object before us, ought to close the sentence. On the
contrary, in drawing up natural characters of a genus,
as well as full descriptions of particular plants, it is
proper to take, in the former imstance, the calyx,
corolla, stamens, pistils, seed-vessel, seed and ‘recep-
tacle; and in the latter, the root, stem, leaves, appen-
dages, flower and fruit, in the order in which they
naturally occur. |

Nomenclature is no less essential a branch of me-
thodical science than characteristic definitions ; for,
unless some fixed laws, or, in other words, good sense
and perspicuity be attended to in this department,
great confusion and uncertainty must ensue.

The vague names of natural objects handed down
to us, in various languages, from.all antiquity, could
have no uniformity of derivation or planin any of those
languages. Their different origins may be imagined,
but cannot be traced. Many of these, furnished by ©
the Greek or Latin, are retained as generic names in
scientific botany, though neither their precise meaning,
nor even the plants to which they originally belonged,
can always be determined, as Rosa, Ficus, Piper, &c.
It is sufficient that those to which they are now, by
common consent, applied, should be defined and fixed.
Botanists of the Linnean school, however, admit no
such generic names from any other language than the
Greek or Latin, all others being esteemed barbarous.
Without this rule we should be.ovewheimed, not only

OF NOMENCLATURE. 283

with a torrent of uncouth and unmanageable words,
but we should be puzzled where to fix our choice, as
the same plant may have fifty different original deno-
minations in different parts of the world, and we might
happen to choose one by which it is least known.
Thus, the celebrated Indian plant now proved beyond
all doubt to be the Cyamus of. Theophrastus*, having
been erroneously reckoned by Linnzus a Nymphea,
received from Gertner, one of the first who well
distinguished it as a genus, the Ceylon name of Ne-
lumbo; which being contrary to all rules of science,
literature, or taste for a generic name, has by others
been made into bad Latin as Nelumbium. But the
universal Hindu name of the plant is Zamara, which,
independent of barbarism, ought to have been preferred
to the very confined one of Nelumbo. In like manner’
the Bamboo, 4rundo Bambos of Linneus, proving a
distinct genus, has received the appellation of Bambusa,
though Jussieu had already given it that of Nastus from
Dioscoridest. Perhaps the barbarous name of some
very local plants, when they cannot possibly have been’

* See Exot. Bot. 2. 1. 60, where the arguments in support of this opi-
nion are given, and Curt. Mag. ¢. 903, where some of them are with
much candour and ingenuity controverted, though not so as to alter
my sentiments; nor can any thing justify the use of Nelumbium ina
scientific work as a generic name. |

+ It is not indeed clear that this name is so correctly applied as that
of Cyamus, because Nastus originally belonged to “a reed with a solid
stem,” perhaps a palm; but not being wanted, nor capable of being cor-
rectly used, for the latter, it may very well serve for the Bamboo. There

_isno end of raking up old uncertainties about classical names. |

984 OF BARBAROUS NAMES.

known previously by any other, and when'that name is
harmoniousand easily reconcileable tothe Latintongue,
may be admitted, as that of the Japan shrub Aucuba ;
but such a word as Ginkgo is intolerable. The Roman
writers, as Cesar, in describing foreign countries, have
occasionally latinized some words or names that fell
in their way, which may possibly excuse our making
Ailanthus of Aylanto, or Pandanus of Pandang.
Still I can only barely tolerate such names out of de-
ference to the botanical merits, not the learning, of
their contrivers; and I highly honour the zeal and
correctness of Mr. Salisbury, who, in defiance of all
undue authority, has ever opposed them, naming
Aucuba, on account of its singular base or receptacle,
Eubasis. I know not how Pandanus escaped his
reforming hand, especially as the plant has already a
good characteristic Greek name in the classical Forster,
Athrodactylis.

Excellent Greek or Latin names are such as indicate
some striking peculiarity in the cenus: as Glycyrrhiza,
a sweet root, for the Liquorice; Amaranthus, without
decay, for an everlasting flower ; Helianthus, ‘a sun-
flower ; Lithospermum, a stony. seed; LHriocalia * a
flower with a singularly woolly base or cup; Origanum,
an ornamental mountain plant; Hemerocallis, a beauty
ofa day; Arenaria, a plant that inhabits sandy places;

* When I named this genus in Exotic Botany, I was not aware of its
having previously been published by M. Billardiere under the name of
Actinotus ; a name however not tenable in Botany, because it has long
been preoecupied in Mineralogy.

GENERIC NAMES IN HONOUR OF BOTANISTS. 285

and Gypsophila, one that loves a chalky soil. Such as
mark the botanical character of the genus, when they
can be obtained for a nondescript plant, are peculiarly
desirable; as Ceratopetalum, from the branched horn-
like petals; Zasiopetalum, from the very singularly
woolly corolla; Calceolaria, from the shoe-like figure
of the same part; Conchiwm, from the exact resem-
blance of its fruit to a bivalve shell.

In all ages it has been customary to dedicate certain
plants to the honour of distinguished persons. Thus
Euphorbia commemorates the physician of Juba a
Moorish prince, and Gentiana immortalizes a king of
Illyria. The scientific botanists of modern times have
adopted the same mode of preserving the memory of
benefactors to their science ; and though the honour
may have been sometimes extended too far, that is no
argument for its total abrogation. Some uncouth names
thus unavoidably deform our botanical books; but
this is often effaced by the merits of their owners, and
it is allowable to model them into grace as much as
possible. Thus the elegant Tournefort made Gundelia
from Gundelscheimer ; which induced me to choose
Goodenia, for my much honoured and valued friend
Dr. Goodenough, now bishop of Carlisle, though it
has, when too late, been suggested that Goodenovia
might have been preferable. Some difficulty has arisen
respecting |rench botanists on account of the ad-
ditional names by which their grandeur, or at least
their vanity, was displayed during the existence of the

286 GENERIC NAMES

monarchy. Hence Pié¢onia was applied to the plant
consecrated to Pitton de Tournefort ; but Linnzus
preferred the namne by which alone he was known out
of his own country, or in learned language, and called
the same genus Journefortia. ‘Thus we have a Fon-
fainesia and a Louichea, after the excellent Louiche
Desfontaines ; but the latter proving a doubtful genus,
or, if a good one, being previously named Péeranthus,
the former is established. We have even in England,
by a strange oversight, both Stwartia and Butea after
the famous earl of Bute; but the former being long
ago settled by Linneus, the latter, since given by
Keenig, is totally inadmissible on any pretence what-
ever, except perhaps in memory of the late marchi-
oness, to whom our gardens are indebted. In likemanner
my own fumea, Evot. Bot. t. 1, has been called in
France Calomeria after the late emperor, by the help
of a pun, though there has long been another genus
Bonapartea, which last can possibly be admitted only
in honour of the divorced empress, and not of her
former consort, who has no botanical pretensions. Our
own beloved sovereign could derive no glory from
the Georgia* of Ehrhart ; but the Strelitzza of Aiton
stands on the sure basis of botanical knowledge and
zeal, to which I can bear ample and very disinterested —
testimony.

Linneus, in his entertaining book Critica Botanica,

* Tetraphis of Wedwig, and Engl. Bot. t. 1020.

IN HONOUR OF BOTANISTS. 987

p. 79, has in several instances drawn a fanciful analogy

between botanists and their appropriate plants, thus,— -
Bauhinia, after the two distinguished brothers John

and Caspar Bauhin, has a two-lobed or twin leaf.

Scheuchzeria, a grassy alpine plant, commemorates
the two Scheuchzers, one of whom excelled in the
knowledge of alpine productions, the other in that of
grasses.

Dorstenia, with its obsolete flowers, devoid of all
beauty, alludes to the antiquated and uncouth book of
Dorstenius.

Hernandia, an American plant, the most beautiful
of all trees in its foliage, but furnished with trifling
blossoms, bears the name of a botanist highly favoured
by fortune, and allowed an ample salary for the purpose
of investigating the natural history of the Western
world, but whose labours have not answered the ex-
pense.- Qn the contrary,

Magnolia with its noble leaves and flowers, and

Dillenia with its beautiful blossoms and fruit, serve
to immortalize two of the most meritorious among
botanists.

Linnea, “ a depressed, abject, Lapland plant, long
overlooked, flowering at an early age, was named by
Gronovius after its prototype Linneus.”

In pursuance of the same idea, Dicksonia, a beautiful
and curious fern, is well devoted to our great crypto-
gamist; Anappia, a small and. singular grass, to an
author celebrated for his minute and curious drawings

288 REMARKS ON

of that tribe; Sprengelia, to one distinguished for
illustrating the impregnation of plants, which the re-
markable form and union of its anthers serve to indi-
cate; while Smthia sensitiva, named by Mr. Dryander
in the Hortus Kewensis of our mutual friend Aiton,
could at that time be merited only by a treatise on the
Irritability of Plants*, to which the specific name
happily alludes.

The generic name being fixed, the specific one is
next to be considered. With respect to this, Rivinus
has the merit of originality, having been the first to
contrive naming each plant in two words. But his
names were meant for specific definitions, for which
they are totally inadequate. Linnzeus, in constructing
his more accurate and full specific characters, intended
the latter should serve as names, and therefore called
them xomina specifica. When he, most fortunately
for the science and for the popularity of his whole
System of Nature, invented the present simple specific
names, he called them nomina trivialia, trivial, or for
common use; but that term is now superfluous.

Specific names should be formed on similar prin-
ciples to the generic ones; but some exceptions are
allowed, not only without inconvenience, but with great
advantage. Such as express the essential specific cha-
racter are unexceptionable, as Banksia serrata, inte-
grifolia, dentata, &c.; but perhaps those which ex-

* Phil. Trans. for 1788.

SPECIFIC NAMES, 989

press something equally certain, but not comprehended
in that character, are still more useful, as conveying
additional information, like Zora alba and coccinea,
Scleranthus annuus and perennis, Aletris fragrans,
Sazrifraga cernua, &c.; for which reasonit is often
useful that vernacular names should not be mere trans-
lations of the Latin ones. Comparative appellations
are very good, as Banksia ericifolia, Andromeda sali-
cifolia*, Savifraga bryoides, Milium cimicinum, Ely-
mus EHystriv, Pedicularis Sceptrum. Names which
express the local situations of different species are ex-
cellent, such as Melampyrum arvense, pratense, ne-
morosum and sylvaticum, Carex arenaria, uliginosa
and sylvatica, as well as aquatica, maritima, rupest7is,
alpina, nivalis, used for many plants. But names de-
rived from particular countries or districts are liable
to much exception, few plants being sufficiently local
to justify their use. Thus Ligusticum cornubiense is
found, not only in Cornwall, but in Portugal, Italy and
Greece ; Schwenkia americana grows in Guinea as
well as in South America. Such therefore, though
sufiered to remain on the authority of Linneus, will
seldom or never be imitated by any judicious writer,
unless Z’rollius européus and asiaticus may justify our
naming the third species of that genus, lately brougiit

* Some botanists write ericefolia, salicisfolia, lingueformis, &c., in-
stead of following the analogy of the Latin in forming adjectives with
an i, as palmifer from palma, @ ; baccifer, from bacca, @; barbiger, fram
barba, @ ; &e.

U

290 SPECIFIC NAMES.

from America, americanus. The use of a plant is
often commodiously expressed in its specific name, as
Brassica oleracea, Papaver somniferum, Inocarpus
edulis; so is likewise its time of flowering, as Primula
weris, Leucojum vernum, estioum and autumnale, and
Helleborus hyemalis.

When a plant has been erroneously made a distinct
genus, the name so applied to it may be retained for
a specific appellation, as Lathrea Phelypea, and
Bartsia Gymnandra; which may also be practised
when a plant has been celebrated, either in botanical,
medical, or any other history, by a particular name,
as Origanum Dictamnus, Artemisia Dracunculus,
Laurus Cinnamomum, Selinum Carvifolia, Carica
Papaya. In either case the specific name stands as a
substantive, retaining its own gender and termination,
and must begin with a capital letter; which last cir- -
cumstance should be observed if a species be called
after any botanist who has more particularly illustrated
it, as Cortusa Matthioli and C. Gmelini, Duranta
Plumierii, and Mutisii. The latter genus suggests an
improvement in such kind of names. ‘The genitive case
is rightly used for the person who founded the genus,
D. Plumierii; D. Mutisiana might serve to commemo-
rate the finder of a species, while D. Eddisia implies the
plant which bears it to have been once called Ellisia.

There is another sort of specific names in the geni-
tive case, which are to me absolutely intolerable, though
contrived by Linneus in his latterdays These are of -

CHANGES OF NAMES. 291

a comparative kind, as Lobelia Columnee, meaning
Columnee formis. We may allow a few such, already
established, to remain, but no judicious author will
imitate them.

Botanists occasionally adapt a specific name to some
historical fact belonging to the plant or to the person
whose name it bears, as Linnea borealis from the
sreat botanist of the north ; Murrea evotica after one
of his favourite pupils, a foreigner ; Browallia demissa
and elata, from a botanist of humble origin and cha-
racter, who afterwards became a lofty bishop, and in
whose work upon water I find the following quotation
from Seneca in the hand-writing of Linneus: ‘‘ Many
might attain wisdom, if they did not suppose they had
already reached it.” In like manner Buffonia tenui-

folia is well known to be a satire on the slender bota-
nical pretensions of the great French zoologist, as the
Hiillia parasitica of Jacquin, though perhaps not
meant, is an equally just one upon our pompous Sir
John Hill. I mean not to approve of such satires.
They stain the purity of our lovely science. If a bo-
tanist does not deserve commemoration, Jet him sink
peaceably into oblivion. It savours of malignity to

make his crown a crown of thorns, and if the applica-
tion be unjust, it is truly diabolical. :

Before I conclude the subject of nomenclature, I
beg leave to offer a few reflections on changes of esta-
blished names. It is generally agreed among mankind
that names of countries, places, or things, sanctioned

Ug

292 RIGHT OF OCCASIONALLY

by general use, should be sacred; and the study. of
natural history is, from the multitude of objects with
which it is conversant, necessarily so encumbered with
names, that students require every possible assistance
to facilitate the attainment of those names, and havea
just right to complain of every needless impediment.
The grateful Hollanders named the island of Mauritius
after the hero who had established their liberty and
prosperity ; and it ill became the French, at that pe-
riod dead to such feelings, to change it, when in their
power, to Isle de France, by which we have in some
late botanical works the barbarous Latin of Znsula
Francie. Nor is it allowable to alter such names,
even for the better. Americo Vespucci had no very
great pretensions to give his own name to a quarter of
the world, yet it is scarcely probable that Columbia
.will ever supersede America. In our science the names
established throughout the works of Linneeus are be-
come current coin, nor can they be altered without
great inconvenience. Perhaps, if he had foreseen the
‘future authority and popularity of his writings, he
might himself have improved upon many which he
adopted out of deference to his predecessors, and itis
in some cases to be regretted that he has not sufficiently
done so. In like manner, the few great leaders in
natural knowledge must and will be allowed to ward
off and to correct, from time to time, all that may de-—
form or enfeeble the prevailing system. They must
choose between names nearly of the same date, and —

=

CHANGING NAMES. 293

~

4

even between good and bad ones of any date. <A
botanist who, by the strength of his own superior
knowledge and authority, reforms and elucidates a
whole tribe of plants hitherto in confusion, as a Hed-
wig in Mosses, or Acharius in Lichens, ought to be
unshackled in every point in which he can be of ser-
vice. His wisdom will be evinced by extreme caution
and reserve in using his liberty with respect to new
names, but more especially new terms; and, after all,
he will be amenable to the general tribunal of bota-
nists, and the judgement of those who come after
him. Few indeed are illustrious enough to claim such
privileges as these. Those who alter names, often for
the worse, according to arbitrary rules of their own,
or in order to aim at consequence which they cannot
otherwise attain, are best treated with silent neglect.
The system should not be encumbered with such
names, even as synonyms. |
When, however, solid discoveries and improvements
are made in the science ; when species or genera have
been confounded by Linnzus himself, and new ones
require to be separated from them, the latter must
necessarily receive appropriate appellations ; as also
when a totally wrong and absurd name has by mistake
been given, as Begonia capensis. In such cases names
must give place to things, and alterations proceeding
from such causes must be submitted to. Thus I believe
Mr. Salisbury has well divided Nymphea. See Annals
of Botany, v. 2.713 also Engl. Bot. t. 2292.

294 COMPOUND

A great and just complaint has arisen in my time
among the cultivators of botany, who found the names
of many garden plants, with which they had long been
conversant, altered for others without any apparent —
cause, and in many instances for the worse ; as dristo-
lochia macrophylla, an excellent and expressive name,
for a very unappropriate one, 4. Szpho. For this I am
obliged to censure my much regretted and very intelli-
gent friend L’Heritier. When he came to England to
reap the rich harvest of our undescribed plants, he
paid no. respect to the generic or specific names by
which Dr. Solander or others had called them, because
those names were not printed; but he indulged him-
self, and perhaps thought he confirmed his own im-
portance, by contriving new ones ; a factitious mode
of gaining celebrity, to which his talents ought to have
been infinitely superior. Nor would it have been easy
to say how far this inconvenient plan of innovation
might have extended, had not the Hortus Kewensis
come forth to secure our remaining property.

I have only to add a few words respecting a kind of
generic names that has of late become more common
‘than Linneeus probably would have approved, though
he has once or twice allowed it: I allude to those com-
pounded either of two established names, or of one —
combined with any other word. Of the former number
is Calamagrostis, formed of Calamus and Agrostis,
two Linnean names ; and this is no where sanctioned
by any good authority. Happily the genus to which it

GENERIC NAMES. 295

has negligently been applied is an drundo. Of the
latter sort is Cissampelos, formed of Cissus, another
established genus, and Ampelos,a Vine ; the latter not
among Linnean names: also Eleagnus, constructed
of two old Greek names, neither of which is now in
botanical use by itself. These are both expressly al-
lowed by Linneus, nor indeed can there be any ob-
jection to the latter. Cissampelos may certainly justify
Hyoscyamus, composed of Cyamus and a word de-
noting swine ; if not, this would prove an objection to
the reestablishment of Cyamus, much more to the
purpose than any that has been advanced ; for /Zyos-
cyamus having been so long and universally used in
systematic botany, could scarcely give place, even to
its venerable prototype. On the same ground only
can several new generic names, used in the fern tribe,
be admitted. ‘These are formed out of Péeris, the
established generic appellation of a common Brake,
with some other Greek word prefixed; as Angiopteris,
a Brake with a capsule, 7meszpteris, a cloven Brake,
and Cenopteris, anew Brake. Whatever may become
of the former two, I must always protest against the
last, given by the celebrated Bergius to the Darea of
Jussieu, on account of its unexampled impropriety. As
well might any new.genus, resembling a Rose, be
called Novarosa; for though the Greek language may
assist us with regard to sound, it can never make
amends for a radical deficiency of sense.

296

CHAPTER XXIII.

ae

EXPLANATION OF THE LINNEAN ARTIFICIAL
SYSTEM.

Tue Linnean System is, as I have already observed,
professedly artificial. Its sole aim is to help any one to
learn the name and history of ar unknown plant in the
most easy and certain manner, by first determiningits. -
Class and Order in this system; after which its Genus
is to be made out by comparing the parts of fructifica-
tion with all the generic characters of that Order; and
finally its Species, by examining all the specific defini-
tions of the Genus. We thus ascertain the generic
and specific name of our plant in Linneus, and under
those we find an enumeration, more or less ample, of
its Synonyms, or the different appellations it has. re-
ceived from other writers, with a reference to figures
in various books ; andas Linnzus always cites Bauhin’s
Pinaxv, which is the common botanical catalogue, or
index to all previous werks, we thus gain a clue to
every thing recorded concerning our plant. Ofall this
mass of information and entertainment we shall find
nothing more concise, luminous, or engaging, either
with respect to the distinctions, uses, or history of
plants, than what is diffused through the various publi- -
cations of Linnzus himself; and the same may, with

t
OF THE LINNZ/AN ARTIFICIAL SYSTEM. 9297

at least equal. truth, be said of those of his works
which illustrate the Animal kingdom. His magic pen
‘turns the wilds of Lapland into fairy land. He has all
the animals of Sweden as much at his call, as our first
parent while the terrestrial paradise was yet in primeval
tranquillity. No writer whatever has rendered the
natural productions, of the happiestand most luxuriant
climates of the globe, half so.interesting or instructive,
as Linneus has made those of his own northern
country.

The Cxasses of the Linnzan System are 24, and
their distinctions are founded on the number, situation,
or proportion oj the Stamens. The Orders are founded
either on the number of the Pistils, or on some cir=
cumstance equally easy, which we shall in due time
explain. ;

The first eleven Classes are characterized solely by
the number of the Stamens, and distinguished by
names, of Greek derivation, expressive of these distinc-
tions.

1: MoNANDRIA. Stamen 1.
A small Class.

Q. DIANDRIA. Stamens 2.
3. TRIANDRIA By
4., TETRANDRIA —— 4.
5. PENTANDRIA Bi

A numerous Class.

6. HEXANDRIA ake 8.

998 LINNEAN

7. HEPTANDRIA Stamens 7.
A very small Class.

8. OCTANDRIA 8.
9. ENNEANDRIA -——— 9.
A small Class.
10. DECANDRIA. ——— 10.
11. DoDECANDRIA ———— 12 to 19.
12. IcosANDRIA =——— 20 or more Stamens,

inserted into the Calyx. Here we first find the |
situation of the Stamens taken into consideration.
They grow out of the sides of the Calyx, often
- from a sort of ring, as in the Strawberry. This is
truly anatural Class, as are several of the following
ones; so that in these instances the Linnean method
of arrangement performs more than it promises. The |
character of this Class is the more important, as such
a mode of insertion indicates the pulpy fruits which
accompany it to be infallibly wholesome, and this
holds good, not only when the stamens are nume-
rous, but in allother cases. Thus Ribes, the Cur-
rant and Gooseberry genus, whose five stamens grow
out of the calyx, stands in the fifth Class, a whole-
~ some fruit, among many poisonous berries: No
traveller in the most unknown wilderness need
scruple to‘ eat any fruit whose stamens are thus
situated; while on the other hand he will do well
to be cautious of feeding on any other parts of the ~
plant. ,

CLASSES. 299

13. POLYANDRIA. Stamens numerous, commonly
more so than in the last Class, and imserted into the
Receptacle, or base of the flower, as in the Poppy,
Anemone, &c. The plants of this fine and nume-
rous Class are very distinct in nature, as well as
character, from those of the Jcosandria.

14. DipYyNAMIA. Stamens two long and two short.
Here proportion comes to our assistance. This is a
natural Class, and contains most of the Labiate,
Ringent or Personate flowers, as the Dead-nettle,
Snap-dragon, Fox-glove, &c.

15. TETRADYNAMIA. Stamens, four long and two
short. A very natural Class, comprehending all the
Cruciform flowers, as the Wall-flower, Stock, Ra-
dish, Mustard, &c. Cleome only does not properly
belong to the rest.

16. MONADELPHIA. Stamens united by their fila-
ments, more or less extensively, into one tube, as
the Mallow tribe, in which such union Is very re-
markable, and the Geranium family, in which it is
less evident.

17. DIaADELPHIA. Stamens united into two parcels,
both sometimes cohering together at the base. This
Class consists of Papilionaceous flowers, and is there-
fore natural; except that some such genera, having

~

300 LINNEHAN

distinct Stamens, are excluded, and referred to the
tenth Class, in consideration of their number solely ;
as some ringent flowers with only two Stamens are
necessarily placed, not in the fourteenth Class, but
the second.

18. PoLYADELPHIA. Stamens united into more than
two parcels, as in St. John’s-wort. A small Class,
in some points related to /cosandria.

19. SYNGENESIA. Stamens united by their Anthers
into a tube, rarely by their Filaments also; and the
flowers are Compound. A very natural and ex-
tremely numerous Class. Examples of it are the
Dandelion, Daisy, Sunflower, &c.

_ 20. GYNANDRIA. Stamens united with, or growing
out of, the Pistil; either proceeding from the Germen,
as in Aristolochia, Engl. Bot. t. 398, or from the
Style, as in the Orchis family. ‘The Passion-flower
is wrongly put by Linneus and others into this
Class, as its stamens merely grow out of an elon-
gated receptacle or column supporting the Germen.

21. Monorctra. - Stamens and Pistils in separate
flowers, but both growing on the same plant, or, as
the name expresses, dwelling in one house, as the

Oak, Hazel, and Fir.

< ~ CLASSES. 301

22. DroecrA. Stamens and Pistils not only in separate
flowers, but those flowers situated on two separate
plants, as in the Willow, Hop, Yew, &c.

These two last Classes are natural when the
barren flowers have, besides the difference in their
essential organs, a different structure from the fertile
ones in other respects ; but not so when they have
the sathe structure, because then both organs are
hable to meet in the same flower. In some plants,
as Rhodiola, Engl. Bot. t. 508, each -flower has
always the rudiments of the other organ, though
generally inefficient.

93. POLYGAMIA. Stamens and Pistils separate in some
flowers, united in others, either on the same plant,
or on two or three different ones.

This Class is natural only when the several flowers
have a different structure, as those of Atriplex ; but
in this genus the Pistil of the united flower scarcely
produces seed. Ii, with Linnzus, we admit into
Polygamia every plant on which some separated
barren or fertile flowers may be found among the
united ones, while all agree in general structure, the
Class will be overwhelmed, especially with Indian
trees. I have therefore proposed that regard should
be had to their general structure, which removes all
such inconvenience, and renders the Class much_
more natural. |

302 LINNEAN

-

24. CRYPTOGAMIA. Stamens and Pistils either not
well ascertained, or not to be numbered with any
certainty, insomuch that the plants cannot be re-
ferred to any of the foregoing Classes. Of this
Terns, Lichens, Sea-weeds and Mushrooms are
examples. :

Appendix. PALM, Palm-trees, a magnificent

tribe of plants, chiefly tropical, whose flowers were ~

too little known, when Linneus wrote, to serve the
purposes of classification; but theyare daily clearing
up, and the Palms are found generally to belong to
the Classes Monoecia, Dioecia, or Hevandria.

eee

The OrDERs of the Linnean System are, in the

first thirteen Classes, founded on the number of the .

Styles, or on that of the Stigmas when the Styles are
wanting, which occurs in Viburnum. Such Orders
are accordingly named

MonoGyniaA. __ Style, or sessile Stigma, 1.
DIGYNIA. Styles, or sessile Stigmas, 2.
TRIGYNIA = ————— ———— 3.
ERERAG YN Ab rere
_ PENTAGYNLA ————-—_-—_ —————_ 5.
HEXAGYNIA ——~ ———_-————. 6,
of very rare occurrence.
HEPTAGYNIA ——————-—-—-—_——_ 7,

still more unusual.

ORDERS. 3058

OCTAGYNIA. Styles, or sessile Stigmas, 8,
scarcely occurs at all.

ENNEAGYNIA— 9,
of which there is hardly an instance.
DECAGYNIA ———————-————- 10.
DoDECAGYNIA - —~—-—-——_——- about _ 12.
PoLYGYNIA § ———-—-———————many.

The two Orders of the fourteenth Class, Didynamia,
both natural, are characterized by the fruit, as follows:
1. GYMNOSPERMIA. Seeds naked, almost universally

four, never more.

2. ANGIOSPERMIA. Seeds in a capsule, numerous.

The two Orders of the fifteenth Class, Tetrady-
namia, both very natural, are distinguished ‘by the
form of the fruit, thus:

1.S1ILicuLosa. Fruita Sidicula, Pouch,orroundish Pod.

2. SILiquosA. Fruit a Svdiqua, or long Pod.

The Orders of the sixteenth, seventeenth and eigh-
teenth Classes, Monadelphia, Diadelphia and Poly-
adelphia, are founded on the number of the Stamens,
that is, on the characters of the first thirteen Classes.

The Orders of the great natural nineteenth Class,
_Syngenesia, are marked by the united or separated,
barren, fertile, or abortive, nature of the florets.
1. PoLYGAMIA EQUALIs. Florets all perfect or
united, that is, each furnished with perfeet Stamens,
a Pistil, and one Seed.

304 ; LINNEAN -

9. POLYGAMIA SUPERFLUA. Florets of the disk with

Stamens and Pistil; those of the radius with Pistil

only, but each, of both kinds, forming perfect Seed.

3. POLYGAMIA FRUSTRANEA. Florets of the disk as

in the last; those of the radius with merely an

abortive Pistil, or with not even the rudiments of

any. This is a bad Order, for reasons hereafter to
be explained.

4. -POLYGAMIA NECESSARIA. Floretsof thedisk with
Stamens only, those of the radius with Pistils only

5. POLYGAMIA SEGREGATA. Several flowers, either

simple or compound, but with united anthers, and
with a proper calyx, included in one common calyx.

Linneus has a sixth Order in this Class, named ~
Monogamia, consisting of simple flowers with united

‘anthers; but this I have presumed to disuse, because

the union of the anthers is not constant throughout
the species of each genus referred to it, witness

Lobelia and Viola, while on the contrary several —

detached species in other Classes haveunited anthers,

as in Gentiana, Engl. Bot. t. 20. These reasons, ©

which show the connection of the anthers of a simple

flower to be neither important in nature, norconstant

~

as an artificial character, are confirmed by the plants —

_ of this whole Linnean Order being natural allies —

~

of others in the fifth Class, and totally discordant, —

in every point, from the comipodnd ee
flowers.

ORDERS. 305

The Orders of the twentieth, twenty-first and
twenty-second Classes are distinguished by the charac-
_ ters of someof the Classes themseives which precede
them, that is, almost entirely by the number of their
Stamens ; for the union of the anthers in some of them
is, for the reasons just given, of no moment.

The Orders of the twenty-third Class, Polygamia,
are, according to the beautiful uniformity of plan which
runs through this ingenious system, distinguished upon
the principles of the Classes immediately preceding.

1. Monoectra has flowers with Stamensand Pistils on
the same plant with others that have only Pistils, or
only Stamens; or perhaps all these three kinds of
blossoms occur; but whatever the different kinds
may be, they are confined to one plant.

2. Droecta has the two or three kinds of flowers-.on
_ two separate plants.

3. TRIOECIA has them on three separate plants, of
which the Fig is the only real example, and in that
the structure of the flowers is alike in all.

The Orders of the twenty-fourth Class, Cryptoga-
mia, are professedly natural. They are four in Lin-
neus, but we now reckon five.

1. Finices. Ferns, whose fructification is obscure,
and grows either on the back, summit, or near the
base of the leaf, thence denominated a frond. See

p. 102.
, X

306 LINNEAN ORDERS.

2. Muscr. Mosses, which have real separate leaves,
and often a stem; a hood-like corolla, or calyptra,
bearing the style, and concealing the capsule, which
at length rises on a stalk with the nie and

opens by a lid.

S. Hepaticm. ~ Liverworts, whose herb is a frond,
being leaf and stem united, and whose capsules do
not open with a lid. Linnzus comprehends this
Order under the iollowing. |

4. ALGE. Flags, whose herb is likewise a frond, and
whose seeds are imbedded, either in its very sub-
stance, or in the disk of some appropriate receptacle.

5. Funct. Mushrooms, destitute of herbage, bearing
their fructification in a fleshy, substance.

Such are the principles of the Linneean Classes and
Orders, which have the advantage of all other systems
in facility, if not conformity to the arrangement of
nature; the latter merit they do not claim. They are
happily founded on two organs, not only essential to a
plant, but both necessarily present at the same time;
for though the Orders of the fourteenth and fifteenth —
Classes are distinguished by the fruit, they can be
Clearly ascertained even in the earliest state of the
germen™.

* An instance apparently to the contrary occurs in the history of
my Hastingia coccinea, Exot. Bot. t. 80, a plant most evidently, both
by character and natural affinity, belonging to the Didynamia Gymno-

+

DIFFICULTIES IN THE LINNZEAN SYSTEM. 307

Tournefort founded his Orders on the fruit ; and his
countryman Adanson is charmed with the propriety of
this measure, because the fruit comes after the flower,
and thus precedence.is given to the nobler part which
distinguishes the primary divisions or Classes! But
happily the laws. of a drawing-room do not extend to
philosophy, and we are allowed to prefer parts which
we are sure to meet with at one and the same moment,
without waiting a month or two, after we have made
out the Class of a plant, before we can settle its Order.

The Linnean System, however, like all human in-
ventions, has its imperfections and difficulties. If we
meet in gardens with double or monstrous flowers,
whose essential organs of fructification are deformed,.
multiplied, or changed to petals; or if we find a soli-.
tary barren or fertile blossom only; we must be at a
loss, and in such cases could only guess at a new plant
_ from its natural resemblance to some known one. But
the principal imperfection of the System in question
consists, not merely in what arises from variations in
number or structure among the parts of a flower,
against which no system could provide, but in the dif-
spermia, but as I could nowhere find it described in that Order, I
concluded it to be unpublished ; and was not a little surprised to be
told some time afterwards, that it was extant in the works of my
friends Retzius and Willdenow, under Didynamia Angiospermia, by the
name of Holmskioldia, after a meritorious botanist. This last name
therefore, however unutterable, must remain; and I wish the Lin-

nean system, as well as myself, might be as free from blame in all
other cases as in this.

x Q@

308 DIFFICULTIES IN THE LINNZEAN SYSTEM.

ferences which sometimes occur between the number
of Stamens, Styles, &c., in different plants of the same
natural genus. Thus, some species of Cerastium have
only four, others five, Stamens, though the greater part
have ten. Lychnis dioica hasthe Stamenson one plant,
the Pistils on another, though the rest of the genus has
them united in the same flower; and there are several
similar instances ; for number in the parts of fructifi-
cation is no more invariable than other characters, and
‘even more uncertain than such as are’ founded on in-
sertion, or the connexion of one part with another.

Against these inconveniences the author of this System
has provided an all-sufficient remedy. At the head of
every Class and Order, after the genera that properly
‘belong to them, he enumerates, in italics, all the ano-
amalous species of genera stationed in other places,
which, by their own peculiar number of Stamens’ or
Styles, should belong to the Class or Order in question,
but which are thus easily found with their brethren by
‘means of the index.

It is further to be observed, that Linneus, ever |
aware of the importance of keeping the natural affini-
tics of plants in view, has in each of his’ artificial
Orders, and sections of those Orders, arranged’ the
genera according to those affinities; while at the head
~ of each Class, in his Systema Vegetabilium, he places’
the same genera according to their technical characters ;
thus combining, as far as art can keep pace with nature,
the merits of a natural and an artificial system. His’

NATURAL SYSTEM OF JUSSIEU. $09

editors have seldom been aware of this; and Murray
especially, in his fourteenth edition of the book just
mentioned, has inserted new plants without any regard
to this original plan of the work.

From the foregoing remarks it is easy to compre-
hend what is the real and highly important use of the
Genera Plantarum of Jussieu arranged in Natural
Orders, the most learned botanical work that has ap-
peared since the Species Plantarum of Linnzus, and
the most useful to those who study the philosophy of
botanical arrangement. The aim of this excellent.
author is to bring the genera of plants together, as
much as possible, according to their natural affinities;
constructing his Classes and Orders rather from an
enlarged and general view of those affinities, than from
technical characters, previously assumed, for each Class
or Order; except great and primary divisions, derived
chiefly from the Cotyledons, the Petals, and the inser-
tion of the Stamens. But his characters are so far from
absolute, that at the end of almost every Order we find
a number of genera merely related to it, and not pro-
perly belonging to it;-and at the end of the system a
very large assemblage of genera incapable of being re-
_ ferred to any Order whatever. Nor could a learner
possibly use this system as a dictionary, so as to find
out any unknown plant. The characters of the Orders
are necessarily, in proportion’as those Orders are na-
tural, so widely and loosely constructed, that a student
has no where to fix; and in proportion as they are

310 SYSTEM OF JUSSIEU.

here and there more defined, this, orany other system,

becomes artificial, and liable to the more exceptions.

The way therefore to use this valuable work, so as to.
ascertain an unknown plant, is, after turning to the

Order or Genus to which we conceive it most probably

allied, to read and study the characters and observa-
tions there brought together, as well as all to which

they may allude. We shall find we learn more from

the doubts and queries of Jussieu than from the asser-
tions of most other writers. We shall readily perceive

whether our plant be known to him or not; and if at
the same time we refer it, by its artificial characters, to

- the Linnean System, we can hardly fail to ascertain,

even under the most difficult circumstances, whether it
be described by either of these authors. A student
may acquire a competent knowledge of natural orders,

with very great pleasure to himself, by repeatedly turn-
ing over the work of Jussieu with any known plants in
his hand, and contemplating their essential generic
characters in the first place, and then what regards
their habit and affinities; proceeding afterwards to
combine in his own mind their several points of agree-
ment, till he is competent to form an idea of those
assemblages which constitute natural Classes and Or-
ders. ‘This will gradually extend his ideas; whereas
a contrary mode would only contract them, and his
Jussieu would prove merely an artificial guide, without
the advantages of facility or perspicuity.

311

CHAPTER XXIV.

ILLUSTRATIONS OF THE LINNZXAN CLASSES AND
~ ORDERS.

I procern toa compendious view of the Linnean
Classes and Orders, which will serve to illustrate many
things in the preceding pages. —

ert ee

Crass 1. Monandria. Stamen 1.
This contains only two Orders.

1. Monogynia. Style 1. Here we find the beautiful
exotic natural order called Scitaminee, consisting
of Cardamoms, Ginger, Turmerick, &c., hitherto a
chaos, till Mr. Roscoe, ina paper printed in the
eighth volume of the Linnean Society's Transactions,
reduced them to very natural and distinct genera by
the form of the filament. See vot. Bot. t. 102,
103, 106—8.

Salicornia, Engl. Bot. t. 415 and 1691, and

_ Hippuris, t.763, are British examples of Monandria
Monogynia. —

Valeriana (Class $) has some species with one »

stamen, | .

2. Digynia. Styles 2. Contains Corispermum, FF.

i)

9, DIANDRIA. TRIANDRIA.

Gre@c.t. 1, Blitum, Curt. Mag. t. 276, and a few
plants besides.

CLAss 2. Diandria. Stamens 2. Orders 3.

. Monogynia. This, the most natural and numerous

Order, comprehends the elegant and fragrant Jas-
mine, the Jasmine, Lilac, Olive, &c.—also Ve-
ronica, Engl. Bot. t. 2, 1027, 623, 783, &c.—and
a few labiate flowers with naked seeds, as Salvia,
Engl. Bot. t. 153, 154, Rosemary, &c., natural
allies of the fourteenth class; but having only two
stamens, they are necessarily ranged here in the
artificial system.

. Digynia consists only of Anthoranthum, a grass,

Engl. Bot. t. 647, which, for the reason just given,
is separated from its natural family in the third class,

. Lrigynia—has only Piper, the Pepper, a large

tropical genus.

Crass. 3. Triandria.. Stamens 3. Orders 3.

» Monogynia. Valeriana, Engl. Bot. t. 698, 1591

and 1531, is placed here because most of its species
have three stamens. See Class 1. Here also we
find the sword-leaved plants, so amply illustrated in
Curtis’s Magazine, Lris, Gladiolus, Ivia, &c., also
Crocus, Lingl. Bot. t. 343, 344, 491, and nume-
rous grass-like plants, Schenus, Cyperus, Scirpus,
see Il. Grec. v. 1, and Engl. Bot. t. 950, 1309,
542, 873, &c.

TRIANDRIA. SES

2. Digynia. This important Order consists of the
true Grasses; seep. 99. Their habit is more easily
perceived than defined; their value, as furnishing
herbage for cattle, and grain for man, is sufficiently
obvious. No poisonous plant is found among them,
except the Lolium temulentum, Engl. Bot.t. 11924,
said to be intoxicating and pernicious in bread. Their
genera are not easily defined. Linnzeus, Jussieu, and
most botanists, pay regard to the number of flerets
in each spikelet; but in Arundo this is of no mo-
ment. Magnificent and valuable works on. this
family have been published in Germany by the cele-
brated Schreber and by Dr. Host.. The Fl. Greca
also is rich in this department, to which the late
Dr. Sibthorp paid great attention, Much is to be
expected from scientific agriculturists ; bat Nature
so absolutely, in general, accommodates each grass
to its own soil and station, that nothing is more
dificult than to overcome their habits, insomuch
that few grasses can be generally cultivated at plea-
sure.

3. Trigyaia is chiefly composed of little pink-like
plants, or, Caryophyllee, as Holosteum, Engl. Bot.

t. 27. | isa
Tillea muscosa, t. 116, has the number proper
to this order, but the rest of the genus bears every
part of the fructification in fours. This in Linnean
language is expressed by saying the flower of 7’/lea

a

314 TETRANDRIA.

- is guadrifidus™, four-cleft, and 7’. muscosa excludes,

3s)

or lays aside, one fourth of the fructification.

Crass 4. Tetrandria. Stamens 4. Orders 3.

Monogynia. A very numerous and various Order,
of which the Proteacee make a conspicuous part,
consisting of Protea, Banksia, Lambertia, Em-
bothrium, &c. See Botany of New Holland, t.7
—10. Scabiosa, Engl. Bot. t.659; Plantago,
t. 1558, 1559, remarkable for its capsula circum-
scissad, a membranous capsule, separating by a com-
plete circular fissure into two parts, as in the next ©
genus, Centunculus, t. 531; Rubia, t. 851, and
others of its natural order, of whose stipulation we
have spoken, p. 167, are found here, and the curious
Epimedium, t. 438. |

. Digynia. Buffonia, t. 1313.

Cuscuta, placed here by Linnzeus, is best removed
to the next class.

. Letragynia. . Ilex, t. 496, a genus sometimes

furnished with a few barren flowers, and therefore
removed by Hudson to the twenty-third Class, of
which this measure serves only to show the disad-
vantage ; Potamogeton, t. 168, 376, and Ruppia,
¢. 136, are examples of this Order. They all have
sessile stigmas.

* See Linn. Sp. Pl. 186, and Curt. Lond. fusc. 6. t. $1.

PENTANDRIA. Re B it |

Crass 5. Pentandria. Stamens 5. A very large class.
Orders 6. |
1. Monogynia. One of the largest and most important
Orders of the whole.system. The genera are enume-
rated first artificially, according to the corolla being
of one petal or more, or wanting; inferior or supe
rior; with naked or covered seeds; but stand in
the system according to their affinities, and compose
some natural orders; as Asperifolie, rough-leaved
plants, which have a monopetalous inferior corolla,
and four naked seeds, with always more or less of
spinous bristles or callous asperities on their foliage;
see Borago, Engl. Bot. t. 36, Lycopsis, t. 938,
and Echium, t.181. Next comes that most elegant
tribe of spring plants denominated Precie by Lin-
neus, Primula, t.4—6, Cyclamen, t. 548, the
charming alpine 4retia, and Androsace, Curt. Mag.
?. 743. ‘These are followed by another Linnean
order, nearly akin, called Rotacee, from the wheel-
shaped corolla, Hottonia, Engl. Bot. t. 364, Lysi-
machia, t. 761.—Convolculus and Campanula, two
large well-known genera, come afterwards; then
Lobelia, t. 140, Impatiens, t. 937, and Viola,
t. 619, 620, brought hither from the abolished
Linnean order Syngenesia Monogamia. The Lu-
ride follow, so called from their frequently dark,
gloomy aspect, indicative of their narcotic and very
dangerous qualities; as Datura, t. 1288, Hyos-
cyainus, t. 591, Atropa, t. 592, and Nicotiana, or

316 PENTANDRIA.

Tobacco. Ina subsequent part we meet with the
Vine, Currant and Ivy, and the Order finishes with
some of the natural family of Contorte, so called
from their oblique or twisted corolla, and which are
many of them very fine plants, as Vinca, ¢. 514,
917. They often abound with milky juice, gene-
rally highly acrid; but Dr. Afzelius net with a
shrub of this order at Sierra Leone, the milk, of
whose fruit was so sweet, as. well as copious, as to
be used instead of cream for tea. ‘This is certainly
what no one could have guessed from analogy. Gar-
deniais erroneously reckoned acontorta by Linneus.

. Digynia begins with the remainder of the Con-

torte; then follow some incomplete flowers, as
Chenopodium, t. 1033, Beta, t. 285, and afterwards
the fine alpine genus of Gentiana, t. 20, 493, 896,
famous for its extreme bitterness and consequent
stomachic virtues. |

The rest of the Order consists of the very natural
Umbelliferous family characterized by having five
superior petals, and a pair of naked seeds, suspended
vertically, when ripe, from the summit of a slender
hair-like receptacle. Of the inflorescence of this

: tribe, and the difficulties attending their generic di-

stinctions, we have spoken, p. 236. In Eryngium,
t.718 and 57, the umbel is condensed into a
cupitulum, or conical scaly head, showing an ap-
proach towards the compound flowers, and accom-

PENTANDRIA. 317

panied, as Jussieu observes, by the habit of a Thistle.
Lagoecia is justly referred to this natural order by
the saine writer, though it has ey a solitary seed
and style.

The Umbellifere are mostly herbaceous; the
qualities of such as grow on dry ground are aro-
matic, while the aquatic species are among the most
deadly of poisons; according to the remark of
Linneus, who detected the cause of a dreadful dis-
order among horned cattle in Lapland*, in their
eating young leaves of Cicuta virosa, Engl. Bot.
¢. 479, under water.

Botanists in general shrink from the study of the
Umbellifere, nor have these plants much beauty in
the eyes of amateurs; but they will repay the
trouble of a careful observation. The late M. Cusson
of Montpellier bestowed more pains upon them than
any other botanist has ever done; but the world
has, as yet, been favoured with only a part of: his
remarks. His Jabours met with a most ungrateful
check, in the unkindness, and still mcre mortifying
stupidity, of his wife, who, during his absence from
home, is recorded to have destroyed his whole her-
barium, scraping off the dried specimens, for the
sake of the paper on which they were pasted !

. Trigynia is illustrated by the Elder, the Sumach
or Rhus, Viburnum, &c., also Corrigiola, Engl.

* See his Tour in Lapland, v. 2. 136.

313 HEXANDRIA.

Bot. t. 668, and Tamariz, t. 1318, of which last
one species, germanica, has ten stamens.

4. Tetragynia has only Evoloulus, nearly allied, to
Convolvulus, and the elegant and curious Parnassia,

t. 82.

5. Pentagynia contains Statice, t. 226, 102, and 328,
a beautiful maritime genus, with a kind of everlast-
ing calyx. The Flora Greca has many fine species.
Linum or Flax follows; also the curious exotic
Aldrovanda, Dicks. Dr. Pl. 30; Drosera, Engl.
Bot. t. 867—9; the numerous succulent genus
Crassula; and the alpine Sibbaldia, t. 897, of the
natural order of Rosacee.

6. Polygynia. Myosurus, t. 435, a remarkable in-
stance of few stamens (though they often exceed
five) to a multitude of pistils.

Crass 6. Hevandria. Statnens 6. Orders 6.

1. Monogynia. This, as usual, is the most numerous.
The Liliaceous family, with or without a spatha,
called by Linneeus the nobles of the vegetable king-
dom, constitute its most splendid ornament. The
beautiful White Lily is commonly chosen by popular
writers to exemplify the stamens and pistils. The —
less ostentatious genus of Juncus or Rush, which
soon follows, is more nearly allied to the Lilies than
a young botanist would suppose. . Near it stand
several genera which have little affinity to each other,
and of these Capurais a mistake, having been made

HEPTANDRIA. 319.

out of a specimen of Daphne indica, which chanced
to have but six stamens. |

2. Digynia has but few genera. The valuable Oryza,
Rice, of which there now seems to be more than
one species, is the most remarkable. Itis a grass
with six stamens.

3. Trigynia. See Rumer, Engl. Bot. t. 1533, 127,
&c., some species of which have separated flowers;
dofieldia, t. 536; and Colchicum, t. 1383 and 1432.

4. Tetragynia. Petiveria alliacea, a plant the number
of whose stamens is not very constant, and whose
specific name is supposed to allude, not only to its
garlic scent, but also to the caustic humour of the
botanist whom it commemorates.

5. Hevxagynia. An order in Schreber and Willdenow,

contains WVendlandia populifolia of the latter ; with
- Damasonium of the former, a genus consisting of
the Linnean Stratiotes alismoides, Exot. Bot. t. 15.

6. Polygynia. Alisma only—Lngl. Bot. t. 837,
775, &e.

Crass 7. Heptandria. Stamens 7. Orders 4.

1. Monogynia. Trientalis, Exgl. Bot. t. 15, a favour-
ite plant of Linneus; and Asculus, the Horse
Chesnut. Several genera are removed to this order
by late writers.

2. Digynia. Limeum, an African genus only.

8. Tetragynia. Saururus a Virginian plant, Aponc-

320 OCTANDRIA.

geton, placed here by Linnzus, is now properly
removed to Dodecandria. It is an East Indian and
Cape aquatic genus, bearing above the water white
fragrant flowers in a peculiar spike, which is either
solitary or double.

4. Heptagynia. Septas, a Cape plant, very nearly
akin to Crassula, to which Thunberg refers it. If
its character in Linneus be constant with respect to
number, it is very remarkable, having the calyx in
seven deep segments, seven petals, seven germens,
and consequently seven capsules.

— Crass 8. Octandria. Stamens 8. Orders 4.

1. Monogynia. A very various and rich order, con-
sisting of the well-known 7rope@olum or Nasturtium,
whose original Latin name, given from the flavour
of the plant, like Garden Cresses, is now become
its English one in every body’s mouth. The elegant
and fanciful Linnean appellation, equivalent to a
trophy plant, alludes to its use for decorating bowers,
and the resemblance of its peltate leaves to shields,

_as well as of its flowers to golden helmets, pierced
through and through, and stained with blood. See
Linn. Hort. Cliff, 143.—Epilobium, Engl. Bot.
t. 838, 795, &c., with its allies, makes a beautiful
part of this order; but above all are conspicuous —
the favourite Fuchsia, the chiefly American: genus
Faccinium, t. 456, 319, &c.; the immense and
most elegant genus Erica, so abundant in southern

its)

ENNEANDRIA. 321

Africa, but not known in America ; and the fragrant
Daphne, t. 1381, of which last the Levant possesses
many charming species. Acer, the Maple, is re-
moved hither in FU. Brit. from the twenty-third
Class.

. Digynia has a few plants, but little known’; among

them are Galenia africana, and Moehringia mus-
Cosa.

. Lrigynia. Polygonum, t. 436, 509, 941, 1s a genus

whose species differ in the number of their stamens
and styles, and yet none can be more natural.
Here therefore the Linnean system claims our in-
dulgence. Paullinia and Cardiospermum are more
constant. |

a i etragynid. Here we find the curious Paris, t.7,_

and Adowa, t.453. Of the former I have lately
received a new species, gathered by my liberal friend
Buchanan among the mountains of Nepaul.

Crass 9. Enneandria. Stamens 9. Orders 3.

. Monogynia. Of this the precious genus Laurus,

including the Cinnamon, Bay, Sassafras, Camphor,
and many other noble plants, is an example.

. Trigynia has only Rheum, the Rhubarb, nearly

related to Rumer.

. Hevagynia. Butomus umbellatus, Engl. Bot.t.651,

a great ornament to our rivers and pools.
| Y

322 DECANDRIA.

ee 10. Decandria. Stamens 10. Orders 5.

. Monogynia. A numerous and fine assemblage,
we ct with a tribe of flowers more or less cor-
rectly papilionaceous and leguminous, which differ
very materially from the rest of that natural order in
having ten stout, firm, separate stamens. See Cassia,
Curt. Mag. t. 107, 633, and Sophora, t. 167 ; also
Evot. Bot. t. 25—27, and Annals of Botany, v. 1.
501.

The Ruta, Rue, and its allies, now become very
numerous, follow. See Tracts on Nat. Hist. 287.
Dictamnus, vulgarly called Fraxinella, is one of
them. Dionea Muscipula, see p. 133, stands in
this artificial order, as do the beautiful Ka/mia,
Rhododendron, Andromeda, Arbutus and Pi yrola,
Engl. Bot. t. 213, &c.

2. Digynia. Saxifraga, remarkable for having the
germen inferior, half inferior, and superior, in diffe-
rent species, a very rare example. See Engl. Bot.
t. 107, 440, 663, 1009, 500, 501. Dianthus, the
Pink or Carnation tribe, and some of its very distinct _
natural order, Caryophyllee, conclude the Decan-
dria Digynia.

3. Trigyna. The Caryophyllee are here continued,
as Cucubalus, t. 1577, Silene, t. 465, 1398, Are-
naria, t. 189, 512, very prolific and intricate genera
in the Levant. Malpighia and Banisteria, beautiful
plants of the Maple family, which next occur, have
no affinity to the foregoing.

DODECANDRIA. 323

4. Pentagynia. Abounds in more Caryophyllea, as

r®

Lychnis, t. 573, and Cerastium, t. 789, 790.—
Cotyledon, t. 325, Sedum, t. 1319, and Ovalis,
t. 762, are placed here. Some of the last genus
have the filaments united at their base, and there-
fore should belong to the sixteenth class,—another
defect in the artificial system.

. Decagynia. Consists of only Neurada, with

Phytolacca; the latter an irregular genus as to
stamens and styles, which therefore afford good
marks to discriminate the species.

Crass 11. Dodecandria. Stamens 12 to 19.
Orders 6.

. Monogynia. A rather numerous and very various

order, with scarcely any natural affinity between the
genera. Some of them have twelve, others fifteen
or more stamens, which should be mentioned in
their characters. Asarum, Engl. Bot. t. 1083, and
the handsome Lythrum Salicaria, t. 1061, also the
American Snow-drop-tree, Halesia, not rare in our
gardens, may serve as examples of this order. Ster-
culia is very properly removed hither from Gynan-
dria by Schreber and Willdenow, as its stamens are
not inserted above the germen.

. Digynia consists of Heliocarpus, a very rare Ame-

rican tree with a singularly fringed or radiated fruit ;
and Agrimonia, Engl. Bot. t. 1335. The latter

Y¥ @

394 ICOSANDRIA.

might as well have been placed in the next class,
with which it agrees in natural order.

3. Trigyna is chiefly occupied by Reseda, the Migno-
nette, ¢. 320, 321, and Euphorbia, t. 256, 883,
&c., one of the best defined and most natural
genera, of which the punicea, Sm. Ic. Pict. t. 3, is
a splendid exotic species. )

4. Tetragynia, in Schreber and Willdenow, consists
of Calligonum, a genus illustrated by L’Heritier in
the Zransactions of Linn. Society, v. 1; and Apo-
nogeton, already mentioned, p. 319.

5. Pentagynia has Glinus, an insignificant genus; and

© Blackwellia, a doubtful one.

6. Dodecagynia is exemplified in Sempercivoum, the-
Houseleek, Angl. Bot. ¢. 1320, whose styles vary
from twelve to eighteen or twenty. Sempervivum
sediforme, Jacq. Hort. Vind. t. 81, is a Sedum
with a superabundance of parts in the fructification.

'

Linneus confounded it with S. rupestre.

Crass 12. Icosandria. Stamens 20 or more, inserted
into the Calyx. Orders 3.

1. Monogynia consists of fine trees, bearing for the
most part stone fruits, as the Peach, Plum, Cherry,
&c., though the leaves and other parts are bitter,
acrid, and, as we have already mentioned, some-
times very dangerous, owing to a peculiar essential
oil, known by its bitter-almond flavour. See spe-_

j

eS

6

ICOSANDRIA. 325

cimens of this family in Engl. Bot. ¢. 1383, 706,
841, 842. The Myrtie tribe is another natural
order, comprehended chiefly under Jcosandria Mo-
nogynia, abounding in a fragrant and wholesome
aromatic oil. These are plentiful in New Holland.
See Tr. of Linn. Soc. v. 3.255, also Exot. Bot.
t. 42, 59, and 84. Caryophyllus aromaticus,
the Clove, should on every account be removed
hither.

. Pentagynia. In this order it is most convenient

to include such plants as have from two to five
styles, and occasionally, from accidental luxuriance
only, one or two more. An example of it is the
very uatural family of the Pomacee, as Pyrus, the
Apple, Pear, &c., Engl. Bot. t. 179, 350, 337;
and Mespilus, t. 1523, Evot. Bot. t. 18, 85. In
this family some species of the same genus have
five, others three, two, or only one style, and a cor-
responding number of seeds. Spire@a, nearly allied
to it, stands here, most of its species having five
styles, though some have a much greater number ;
see Engl. Bot. t. 284, 960. Mesembryanthemum,
a vast and brilliant exotic genus, of a succulent
habit, abounding in alkaline salt, and a few genera
naturally allied to it, make up the rest of the order.

. Polygynia. An entirely natural order of genuine

~ Rosaceous flowers, except possibly Calycanthus.

Here we find Rosa, Engl. Bot. t. 187, 990—2 ;

3

6 : ICOSANDRIA.

Rubus, t.. 826, 827, 716; Fragaria, t. 1594;
Potentilla, t. 88, 89, 862; Tormentilla, t. 863,
864; Geum, t. 106; Dryas, t.451; and Comarum,
¢. 172: all elegant plants, agreeing in the astringent
qualities of their roots, bark and foliage, and in their
generally eatable, always innocent, fruit. The vege-
table kingdom does not afford a more satisfactory
example of a natural order, composed of natural
genera, than this; and Linneus has well illustrated
it in the Vora Lapponica. His genus Tormentilla,
differing from Potentilla in number of petals and
seements of the calyx, though retained by Jussieu,
may perhaps be scarcely distinct ; yet there is a
difference in their habit, which has induced me to
leave it for further consideration. Haller united
them both with Fragaria and Comarum, which
the character and habit of the latter totally forbid,
and Gertner has well suggested a mark from the
smoothness of the seeds in Fragaria, (as well as
Comarum,) to strengthen that of its pulpy recep-
tacle. Whatever difficulties may attend these genera,
how admirably does the fruit serve us in Mosa,
Rubus, Dryas and Geum, to discriminate those
whose leaves, flowers, and habit all stamp them as
distinct! A student cannot do better than to study
this order and these genera, as an introduction to
the knowledge of more obscure ones; and the beau-
tiful plants which compose it, mostly familiar to
every body, are easily obtained. —

~

POLYANDRIA. 327

Crass 13. Polyandria. Stamens numerous, inserted

into the Receptacle. Orders 7.

1. Monogynia. The genera of this order are artificially

distributed according to the number of their petals,
but not so arranged in the body of the system.
‘They form a numerous and various assemblage of
handsome plants, but many are of a suspected
quality. Among thein are the Poppy, the Caper-
shrub, the Sanguinaria canadensis, Curt. Mag.
¢. 162, remarkable for its orange juice, like our
Celandine, Engl. Bot. t. 1581; also the beautiful
genus Cistus, with its copious but short-lived flowers,
some of which (Zngl. Bot. ¢. 1321) have irritable
stamens ; the splendid aquatic tribe of Nymphea,
&c., ¢. 159, 160,2292. But the precious Nutmeg
and the Tea™ are perhaps erroneously placed here
by Linneus, as well as the Clove; while on the
other hand Cleome more properly belongs to this
part of the system than to the fifteenth Class.

2. Digynia has principally the P@onia, ¢. 1513, va-

riable in number of pistils, and Fothergilla alnifolia,
an American shrub.

3.. Trigynia. Delphiniumthe Larkspur, and Aconitum

the Monk’s hood, two variable and uncertain genera
as to number of pistils.

4. Tetragynia. Tetracera ought, by its name, to

have constantly four pistils, but the rest of this order
* See Monadelphia.

|

328 POLYANDRIA.

are very doubtful. Caryocar, whose large rugged
woody nuts contain the most exquisite kernel ever
brought to our tables, and which is the same plant
with Geertner’s and Schreber’s /¢hizobolus, as the
excellent Willdenow rightly judged, is not certain
in number ; and still less the Cimicifuga ; whilst
Wahlbomiais probably a Tetracera : see Willdenow.

5. Pentagynia contains chiefly Aquilegia the Colum-
bine, and Ngella—both strictly allied to genera in
the third order. Reauwmuria indeed is here well
placed. Some Nigelle have ten styles.

6. Heragynia consists of Stratiotes, Engl. Bot. t. 379;
and Brasenia, a new genus of Schreber’s with which
T am not acquainted.

I would recommend an union of the last five
orders, for the same reason that influenced me in
the preceding class. They now only serve to keep
natural genera asunder, the species of which not
only differ among themselves as to number of pistils,
but each species is often variable besides. ‘The genera
are so few that no inconvenience could arise on that
account. I conceive such reforms, founded in expe-
rience not in theory, serve to strengthen the system,
by greatly facilitating its application to practice.

7. Polygynia. An order for the most part natural,
comprehending some fine exotic trees, as Dzllenia,
Exot. Bot. t. 2, 3, 92 and 93; Liriodendron, the
Tulip-tree ; the noble Magnolia, &c.; a tribe con-

DIDYNAMIA. 399

cerning whose genera our periodical writers are
falling into great mistakes. ‘Io theses succeed a
family of plants, either herbaceous or climbing, of
great elegance, but of acrid and dangerous qualities,
as Anemone, in a single state the most lovely, in a
double one the most splendid, ornament of our par-
terres in the spring; <Aztragene and Clematis, so
graceful for bowers ; Thalictrum, Adonis, Ranun-
culus, Trollius, Helleborus and Caltha, all con-
spicuous in our gardens or meadows, which, with a
few less familiar, close this class.

Nothing can be more injudicious than uniting
these two last classes, as some inexperienced authors
have done. ‘They are immutably distinct in nature
and characters, whether we call the part which im-
mediately bears the stamens in the Jcosandria a
calyx, with most botanists, or a receptacle, with
Mr. Salisbury in the eighth volume of the Linnean
Society’s Transactions, where, among many things
which I wish had been omitted, are some good
remarks concerning the distinction between calyx
and corolla. This the writer in question considers
as decided in doubtful cases by the latter sometimes
bearing the stamens, which the former, in his
opinion, never really does.

Crass 14. Didynamia. Stamens 2 long and 2 short.
Orders 2, each on the whole very natural.

1. Gymnospermia. Seeds naked, in the bottom of

330 DIDYNAMIA.

the calyx, four, except in Phryma, which. has a
solitary seed.—Corolla monopetalous and irregular,
a little inflated at the base, and holding honey,
without any particular nectary. Stamens in two
pairs, incurved, with the style between them, so that
the impregnation rarely fails. The plants of this
order are mostly arematic, and none, I believe,
poisonous. ‘The calyx is either in five nearly equal
segments, or two-lipped. Most of the genera afford.
excellent essential characters, taken frequently from
the corolla, or from some other part. Thus,

Perilla has two styles, of which it is an unique
example in this class.

‘Mentha a corolla whose segments are nearly
equal, and spreading stamens. Engl. Bot. t. 446—8.

Lavandula the Lavender, and /Vestringia, Tracts
on Natural History, 277, t. 3, have a corolla resu-
pinata, reversed, or laid on its back.

Teucrium a deeply divided upper lip, allowing
the stamens and style to project between its lobes.
Engl. Bot. t. 680.

Ajuga scarcely any upper lip atall, ¢.77 and 489.

Lamium has the mouth toothed on each side,
t. 7608. | |

Prunella, t. 961, has forked filaments; Cleonia
four stigmas; Prasium a pulpy coat to its seeds.
These instances will suffice as clear examples of
natural genera, distinguished by an essential tech-
nical character, in a most natural order.

TETRADYNAMIA. 331

2. Angiospermia. Seeds in a capsule, and generally

very numerous.—The plants of this order have the
greatest possible affinity with some families in Pen-.
tandria Monogynia. Some species even vary from
one class to the other, as Bignonia radicans, Curt.
Mag. t: 485, and Antirrhinum Linaria, Engl. Bot.
¢. 658, 260, in which the irregular corolla becomes
regular, and the four unequal stamens are changed
to five equal ones; nor does this depend, as has
been asserted, on the action of any extraneous pollen
upon the stigmas of the parent plant, neither are.
the seeds always abortive. No method of arrange-
ment, natural or artificial, could provide against such
anomalies as these, and therefore imperfections must
be expected in every system.

Crass 15. Tetradynamia. Stamens 4longand 2 short.

i.

2

Orders 2, perfectly natural. Flowers cruciform.

Stliculosa. Fruita roundish pod, or pouch. In
some genera it is entire, as Draba, Engl. Bot.
t. 586, and the Honesty or Satin flower, Lunaria:
in others notched, as Thlaspi, t. 1659, and Lberis,
¢. 52; which last genus is unique™ in its natural

order in having unequal petals. Crambe, t. 924;

Isatis, t. 97; and Bunias, t,231; certainly belong to
this Order, though piaced by Linneus in the next.

. Siliquosa. Fruita very long pod. Some genera

have a calyx clausus, its leaves slightly cohering by
* Except one species of Teesdalia, Sim. Compend. ed. 3. 98.

32, MONADELPHIA.

their sides, as Raphanus, t. 856; Cheiranthus,
t. 462; Hesperis, t.731; Brassica, t. 637, &c.
Others have a spreading or gaping calyx, as Car-
damine, t. 1000; Stsymbrium, t. 855; and espe-
cially Stnapis, t. 969 and ¢. 1677.

Cleome is a very irregular genus, allied in habit,
and even in the number of stamens of several
species, to the Polyandria Monogynia. Its fruit,
moreover, is a capsule of one cell, not the real two-
celled pod of this Order. Most of its species are
foetid and very poisonous, whereas scarcely any plants
properly belonging to this Class are remarkably
noxious, for I have great doubts concerning the dis-
ease called Raphania, attributed by Linneus to the
seeds of Raphanus Raphanistrum.

The Cruciform plants are vulgarly called antiscor-
butic, and supposed to be of an alkalescent nature.
Their essential oil, which is generally obtainable in
very small quantities by distillation, smells like vola-
tile alkali, and is of a very acrid quality. Hence the
foetid scent of water in which cabbages, or other
plants of this tribe, have been boiled.

Cxiass 16. Monadelphia. Stamens united by their

ii

filaments into one tube. Orders 8, distinguishe
by the number of their stamens. .

Triandriais exemplified by Stsyrinchium, Ic. Pict.
t. 9, and Ferraria, Curt. Mag. t. 144, 532, both
erroneously placed by Linnzeus in Gynandria. Also

MONADELPHIA. 333

the singular Cape plant dphyteia, consisting of a
large flower and succulent fruit, springing imme-
diately from the root, without stem or leaves. On
this plant Linnzus published a dissertation in 1775.
Tamarindus has lately been removed hither from
the third Class, perhaps justly. |

. Pentandria. Erodium, Engl. Bot. t. 902, sepa-
rated, with great propriety, from Geranium by
LHeritier; Hermannia, a pretty Cape genus, Curt.
Mag. t. 307; and a few other plants, more or less
akin to the Mallow tribe, compose this Order; to
which also strictly belong some species of Linum,
Geranium, &c. Passiflora, removed from Gynan-
dria, belongs most unquestionably to Pentandria
Trigynia, and by no means to this Class.

. Heptandria consists only of Pelargonium of L’He-
ritier, an excellent genus, comprising most of the
Cape Geraniums, and marked by its irregular flower,
seven stamens, and tubular nectary.

. Octandria contains Aitonia, Curt. Mag. t. 173,
named in honour of the excellent and universally
respected author of the Hortus Kewensis. Pistia
is, I believe justly, placed here by Schreber and
Willdenow. |

. Decandria. Geranium, properly socalled, Engl.
Bot. t.404, 405, 272, &c., is the principal genus
here. The late Professor Cavanilles, however, in
his Dissertationes Botanice, referred to this Order

334 MONADELPHIA.

NI

a vast number of genera, never before suspected to
belong to it, as Bannisteria, Malpighia, Turrea,
Melia, &c., on account of some fancied union of
their filaments, perhaps through the medium of a
tubular nectary ; which principle is absolutely inad-
missible ; for we might just as well refer to Mona-
delphia every plant whose filaments are connected
by insertion into a tubular corolla. Some species of
Ovalis, see p. 323, belong to this Order; as do
several papilionaceous genera, of which we shall
speak under the next Class.

. Eindecandria contains only the splendid South-

American genus Brownea, the number of whose
stamens is diiferent in different species.

. Dodecandria, Stamens mostly fifteen, is composed

of some fine plants allied to the Mallows, as Ptero-
spermum, Curt. Mag. t. 620, Pentapetes, &c.

. Polyandria, a very numerous and magnificent

Order, comprises, among other things, the true
Columnifere or Malvacee, as Malva, Engl. Bot.
t.671, 754, Althea, t. 147, Mbiscus, Spicit. Bot.
t. 8, Gossypium the Cotton-tree, Alcea the Holly-
hock, &c. Stately and beautiful plants of this
Order, though not Malvacee, are Carolinea, whose
angular seeds are sold in our shops by the name of
Brasil nuts; Gustavia, named after the late King of
Sweden, a great patron of botany and of Linneus;
Camellia, Curt. Mag. t. 42, whose splendid varie-

DIADELPHIA. 335

“ties have of late become favourites with collectors ;
Thea, the Tea-tree, its near relation, placed by
Linneus in Polyandria Monogynia*; Stuartia,
Hvot. Bot. t. 110; and Barringtonia, the original
Commersonia, Sonnerat Voy. a la Nouv. Guinée,
£3, 9: |

Cuass 17. Diadelphia. Stamens united by their
filaments into two parcels, both sometimes cohering
at the base. Orders 4, distinguished by the number
of their Stamens. Flowers almost universally papi-
lionaceous.

1. Pentandria. The only genus in this Order is
Monnieria, Lamarck t. 596, a rare little South
American plant, whose natural order is uncertain.
It has a ringent corolla, ternate leaves, a simple
bristly pubescence, and is besprinkled with resinous
dots.

9, Hevandria. Saraca, in this Order, is as little
known as the Monnieria, except that it undoubtedly
belongs to the leguminous family. It seems most
allied to Brownea, Jonesia, Afzelia, &c. Fumaria,
the only genus besides, is remarkable for the great
variety of forms in its seed-vessel, whence botanists
who make genera from technical characters, without ©
regard to natural principles, have injudiciously sub-

* The observations of Dr. Kendrick, of Warrington, have determined
the class of this interesting plant, muchto oar satisfaction.

336 DIADELPHIA.

divided it. See Engl. Bot. t. 588—3590, 943,
1471. |

3. Octandria. Polygala, t.'76, is the principal genus
here. America and the Cape of Good Hope abound
in beautiful species of it, and New Holland affords
some new genera, long confounded with this. Dal-
bergia is perhaps as well placed in the next Order.

4. Decandria is by far the most numerous, as well as
natural, Order of this Class, consequently the genera
are difficult to characterize. ‘They compose the
family of proper Papilionacee or Leguminosa@, the
Pea, Vetch, Broom, &c. ‘Their stamens are most
usually nine in one set, with a single one separate.

The genera are arranged in sections variously cha-
racterized. |

* Stamens all united, that is, all in one set. ‘The
plants of this section are really not diadelphous but
monadelphous. See Spartium, Engl. Bot. i, Jonge
Some of them, as Lupinus, and Ulez, t. 742, 743,
have indeed the tenth stamen evidently distinguished
from the rest, though incorporated with them by its
lower part. Others have a longitudinal slit in the
upper side of the tube, or the latter easily separates
there, as Ononis, t. 682, without any indication of a
separate stamen. Here therefore the Linnean System
swerves from its strict artificial laws, in compliance
with the decisive natural character which marks the
plants in question. We easily perceive that character,

DIADELPHIA,. Jor

and have only to ascertain whether any papilionaceous
plant we may have to examine has ten stamens, all
alike separate and distinct, in which case it belongs to
_ the tenth Class, or whether they are in any way com-
bined, which refers it to the seventeenth.

** Stigma downy, without the character of the pre-
ceding section, for this and all the following are truly
diadelphous. Very nice, but accurate, marks distin-
guish the genera, which are sufficiently natural. The
styleand stigma afford the discriminative characteristics
ot Orobus, t. 1153; Pisum, t. 1046; Lathyrus, t. 670,
1108; Vicia, t. 334, 481—483; and no less deci-
sively in Hrewm, t. 970, 1223, which last genus, not-
withstanding the remark in Jussieu 360, “ stigma non
barbatum,” (taken probably from no genuine species,)
most evidently belongs to this section, as was first re-
marked in the Fora Britannica; and it is clearly
distinguished from all the other genera of the section
‘by the capitate stigma hairy all over; nor is any
- genus in the whole Class more natural, when the
’ hitherto mistaken species are removed to their proper

places. See FV. Brit. |

wes Legume imperfectly divided into two cells,

always, as in all the following, without the character

of the preceding sections. This is composed of the

singular Biserrula, known by its doubly serrated fruit,

of which there is only one species; the Phaca, Jacq.

Le. Rar. t. 151; and the vast genus of Astragalus,
Zz

338 DIADELPHIA.

Engl. Bot. t. 274, &c., lately illustrated in a splendid |
work by an able French botanist, Decandolle.

were Leoume with scarcely more than. one seed.
Of this Psoralea, Curt. Mag. t. 665; the curious
Stylosanthes of Swartz; the Halla of Thuaberg; and
our own Trifolium, Engl. Bot. t. 1770, 1048—1050,
are examples. The last genus, one of the most natural,
as to habit and qualities, is extremely untractable with
respect to botanical characters. Some species, ¢. 1047,
1340, 1769, have many seeds in each pod; some have
not even the capitate inflorescence, made a part of the
generic definition. The difficulty is lessened by esta-
blishing Aelilotus as a genus, with Jussieu: but the
whole requires to be well reconsidered ; for, if pos-
sible, so great a laxity of definition, with such glaring
exceptions, should not disgrace any system.

wee Tecume composed of single-valved joints,
which are rarely solitary. Hedysarum, t. 96, is the
most important genus of this section, and is known by
its obtuse or rectangular keel. dippocrepis, t. 31;
Ornithopus, t. 369; and Scorpiurus, known in gardens
by the name of Caterpillar, from its worm-like pod,
are further examples. Smithia, Ait. Hort. Kew. t. 13,
is remarkable for having the joints of the legume con-
nected by means of the style, as by a thread ;_ the sta-
mens in two equal divisions, with five anthers to each;
and a two-lipped calyx. Hedysarwmn vespertilionis,
Jacq. Ic. Rar. t. 566, in some points approaches this

DIADELPHIA. 339

genus, and more certain species are possibly latent
among the numerous unsettled papilionaceous plants
of India.

eH Teoume of one cell, with several seeds. To
this belong the genus J¥Zelilotus, if separated from
Trifolium; the Indigofera, several species of which
are so valuable for dyeing blue; the handsome Rodima,
Curt. Mag. t. 311; Cytisus, t. 176, &c.; and Cili-
toria*, Ins. of Georgia, t. 18: also Lotus, Engl. Bot.
t. 995, and Medicago, t. 1616; which last is justly
transferred by Willdenow from the foregoing section
to this.

Papilionaccous plants are rarely noxious to the larger
tribes of animals, though some species of Galega in-
toxicate fish. The seeds of Cytisus Laburnum have
of late been found violently emetic, and those of
Lathyrus sativus have been supposed at Florence to |
soften the bones, and cause death; we know of no
other similar instances in this Class, which is one of
the most abundant in valuable esculent plants. The
Negroes have a notion that the beautiful little scarlet
and black seeds of Abrus precatorius, so frequently
used for necklaces, are extremely poisonous, insomuch
that half of one is sufficient to killa man. ‘This is
totally incredible. Linnzus however asserts rather too
absolutely, that ‘‘ among all the leguminous or papi-

* From xAziw, to close or shut up, in allusion to the situation of
the wings and keel.
Z2

340 POLYADELPHIA.

lionaceous tribe there is no deleterious plant to be
found.”

Cxass 18. Polyadelphia. Stamens united by their
filaments into more than two parcels. Orders three,
distinguished by the number or insertion of their

stamens, which last particular Linneus here over-
looked. |

No part of the Linnzan system has been less accu-
rately defined or understood than the Orders of the
eighteenth Class. Willdenow, aware of this, has made
some improvements, but they appear to me not suf-
ficient, and I venture to propose the following arrange-
‘ment.

J. Dodecandria. Stamens, or rather Anthers, from
twelve to twenty, or twenty-five, their filaments un-
connected with the calyx. Of this the first example
that presents itself is Theobroma, the Chocolate
tree, Merian Surin. t. 26,63, Lamarck Illustr.
t. 635. The flowers have not been seen fresh in
Europe, and we only know them from drawings —
made in the West. Indies, one of which, preserved
in the Linnean herbarium, is my authority for the
following descriptions. ‘The filaments are inserted
between the long tapering segments of a five-cleft
nectary, on its outside, and each bears at its summit —
four sessile, obtuse, spreading anthers. - Aublet’s”
figure of this genus, which Schreber and Willdenow —
seem to have followed, represents but two. The

|

POLYADELPHIA. 34]

fruit is perhaps most properly a berry with a hard
coat, whose seeds, when roasted, make chocolate.
Bubroma of Schreber, Guazuma Lamarck, t. 637,
confounded by Linnzus with the preceding genus,
has similar filaments, but each bears five anthers ;
Jussieu and Cavanilles say three. The fruit is a
woody capsule, with ten rows of perforations.
Abroma, Jacq. Hort. Vind. v. 3. t. 1. Miller
Iilustr. t. 63, has tive parcels of anthers, nearly
sessile on the outside of the nectary, between its
obtuse, reflexed, notched lobes. It is difficult to say
how many anthers compose each parcel, for the dif-

ferent accounts on record are totally irreconcileable. -

We have found three; the drawing sent to Linneus
represents six ; and Miller has a much greater num-
‘ber. Perhaps they may vary. In this uncertainty
’ the genus in question is best placed with its natural
allies in this order, with a reference to it in italics at
the end of Polyadelphia Polyandria. Its fruit is a
membranous winged capsule, opening at the top.
Monsonia, Curt. Mag. t. 73, Lamarck t. 638, re-
moved by Schreber and Willdenow to Monadelphia,
rather, I think, belongs to this class, where Linneeus

placed it. The five filaments, bearing each three.

long-stalked anthers, are merely inserted into a short
meinbranous cup, or nectary, for so the analogy of
the three preceding genera induces us to call it; and
it we refer Monsonia to Monadelphia, we fall into
the error of Cavanilles mentioned p. 333. Last

349 POLYADELPHIA.

Citrus, the Orange, Lemon, &c., Lamarck t. 639,
most unquestionably belongs ‘to this Order. Its
stamens are about nineteen or twenty, combined
variously and unequally in several distinet parcels ;
but those parcels are inserted into a proper recep-
tacle, by no means into the calyx, as the character
of the Class Icosandria indispensably requires. Even
the number of the anthers of Citrus accords better
with most plants in Dodecandria than in Icosandria,
notwithstanding the title of the latter.

2. Icosandria. Stamens numerous, their filaments
inserted (in several parcels) into the calyx.—To
this Order Professor Willdenow properly. refers
Melaleuca, Exot. Bot. t. 34—36, 55, 56, which
had previously stood in Polyandria, botanists having
only considered number and not znsertion in the
Orders of Polyadelphia, whence a double mistake
has arisen, concerning Cztrus on the one hand, and
Melaleuca on the other.

3.. Polyandria. Stamens very numerous, unconnected
with the calyx. This Order consists of several ge-
nera. ‘The most remarkable is Hypericum, Engl.
Bot. t. 109, 1295—1297, &c., whose stamens are
united into three or five parcels, corresponding with —
the number of its styles. Munchhausia is a Lager- —
stromia, nor does it appear'to be polyadelphous at

— all. Linneus seems to have intended bringing Thea
“into this Order ; see Monadelphia Polyandria.

SYNGENESTA. 343 ©

Crass 19. Syngenesia. Anthers united into a tube.
Flowers compound. Orders 5.

This being truly a natural Class, its Orders are
most of them equally so, though some are liable to
exceptions, as will presently be explained.

1, Polygamia @qualis. In this each floret, taken
separately, is perfect or united, being furnished with
its own perfect stamens and pistil, and capable of
bringing its seed to maturity without the assistance
of any other floret. The Order consists of three
sections.

* Florets all ligulate, or strap-shaped, called by
Tournefort semiflosculous. These flowers are generally
yellow, sometimes blue, very rarely reddish. ‘They
expand in a morning, and close towards noon or in
cloudy weather. Their herbage is commonly milky
and bitter. Leontodon, Engl. Bot. t. 510; Trago-
pogon, t. 434, 638; Hieracium, t. 349, &c.; and
Cichorium, t. 539, exemplify this very natural section.

** Flowers globose, generally uniform_and regular,
their florets all tubular, five-cleft, and spreading.
Carduus, t. 973, 976 ; Onopordum, t. 977; and Arc-
tium, t. 1228, well exemplify this. Cardina, t. 1144,
does not so exactly agree with the above definition,
having a flat disk; but its affinity to the other genera
is indubitable. Its flattened disk and radiating coloured
calyx seem contrived to imitate the radiated flowers of
the following Order.

344 SYNGENESIA.

*** Flowers discoid, their florets all tubular, re-
gular, crowded and parallel, forming a surface-nearly
. flat, or exactly conical. Their colour is most generally
yellow, iv some cases pink. Santolina, t. 1413; and
Bidens, t. 1113, 1114, are genuine examples of this
section: Eupatorium, t. 428, and the exotic St@he-_
lina, Dicks. Dr. Pl. 13, approach to the preceding
one. There is however the most absolute difference
between these two sections, collectively, and the first ;
while, on the other hand, they have considerable af-
finity with some of the following Orders, as will be
hereafter explained.

2. Polygamia superflua. Florets of the disk perfect
or united ; those of the margin furnished with pistils
only; but all producing perfect seed.

* Discoid, the florets of the margin being obsolete
or inconspicuous, from the smallness or peculiar form,
of the corolla; as Artemisia, Engl. Bot. t. 338,978,
1930; Tanacetum, t. 1229; Conyza, t. 1195; and
Gnaphalium, t. 267, 1157. In the last the marginal
. florets are mostly five-cleft and tubular like the rest,
only wanting stamens. Caution is requisite to detect
the difference between this section and the preceding
Order. :

** Tieulate, two-lipped, of which Perdicium, a
rare exotic genus, is the only instance.

*** Radiant, the marginal florets ligulate, forming
spreading conspicuousrays; as Bellis the Daisy, 7.424;

SYNGENESIA. 345

Aster, t. 87, a very numerous genus in America;
Chrysanthemum, t. 601, 540; Inula, t. 1546, &c.
This section seems, at first sight, a combination of the
first and third sections of the former Order, but this is
chiefly in the form of its corollas. It is rather an ap-
proach of that third section towards what is equivalent
to becoming double in other tribes. Accordingly, the
Chamomile, Anthems nobilis,t.980; Chrysanthemum
Leucanthemum, t.601 ; and some others, occasionally
have their whole disk changed to ligulate white florets,
destitute of stamens, and consequently abortive. Such
are actually called double flowers in this Class, and
very properly. Many exotic species so circumstanced
are met with in gardens. A few very strange anomalies
occur in this section, as already mentioned, p. 233,
one Sigesbeckia having but three stamens, instead of
. five, the otherwise universal number in theClass; and
Tussilago hybrida, t. 430, as well as paradora of
Retzius, having distinct anthers. Nature therefore,
even in this most natural Class, is not quite without
exceptions.

3. Polygamia frustranea. Florets of the disk, as in
the preceding, perfect or united ; those of the margin
neuter, or destitute of pistils as well as of stamens ;
only some few genera having the rudiments of pistils
in their radiant florets.

This Order is, still more evidently than the last,
analogous to double flowers of other Classes. Ac-

346 SYNGENESIA.

cordingly, Coreopsis is the very same genus as
Bidens, only furnished with unproductive radiant
florets. C. bidens of Linnzus is the same species
as his B. cernua; C. coronata is his B. frondosa ;
and C. leucantha, B. pilosa. Some species of
Coreopsis indeed have never been found without
rays. Linneus expresses his difficulties on this
subject in Phil. Bot. sect. 209, but seems inclined
to unite the two genera. A similar ambiguity occurs
between Gorteria and Atractylis, Relhania (of the
Jast Order) and Athanasia, and in some degree
between Centaurea, Engl. Bot. t. 278, 1678, 56,
&c., and Carduus, or Serratula; only the scales of
the calyx of Centaurea generally keep that genus
distinct. | |
I should be much inclined to abolish this Order.
Those of its genera which have rudiments of pistils
in their radiant florets, as Rudbeckia and Helianthus,
would very commodiously range with their near
relations in Polygamia superflua, nor are we sure
that such radiant florets are in all cicumstances
abortive, neither can a student often know whether
they are so or not. It does not follow, from what
has just been observed, that the presence of radiant
florets, whether abortive or not, can never afford a
‘ generic character, provided there be no correspond-
ing genus without them. ‘This must be determined
by experience and observation. They are indeed to
be considered as a very secondary mark, the most

SYNGENESIA. 347

“essential in this Class being derived from the recep-
tacle, crown of the seed, and calyx. These Gertner
has illustrated with the greatest accuracy and skill,

but even these must not be blindly followed to the
destruction of ne tiiret genera.

. Polygamia necessaria. Florets of the disk fur-
nished with stamens only; those of the margin, or
radius, only with pistils; su.that both are necessary
‘to-each other. This is well seen in the common
Garden Marigold, Calendula, in whose calyx, when
ripening seed, the naked and barren disk is conspi-
cuous. Othonna, Curt. Mag. t. 306, 768, Arctotis,
Osteospermum and Si/phium, not rare in gardens,
are further examples of this Order, which I believe
is constant and founded in nature. We have no
British specimens either of it or the following.
Filago, at least as far as our Flora is concerned,
belongs to Gnaphalium. See Engl. Bot. t. 946,
1193, &c.

. Polygamia segregata. Several flowers, either
simple or compound, but with united tubular anthers,
and with a partial calyx, all included in one general
calyx. Of these the Globe-thistle, Echinops, and
Stoebe, with Seriphium and Corymbium, (which
two last require to be removed hither from the
abolished Linnzan Order Syngenesia Monogamia,)
have only one floret in each partial calyx ; Jungia
has three, Elephantopus four, others more. In

348 GYNANDRIA.

every case the partial calyx is distinguished from
the chaffy seed-crown observable in several genera
of the other Orders, (though the latter is indeed
analogous to a calyx,) either by being inferior, or
by the presence of a seed-crown, or feathery down,
besides. See Lamarck, t.'718—723, where the

plants in question are well represented.

Cass 20. Gynandria. Stamens inserted either upon
the style or germen. Orders 9 in Linnzeus, but
some alterations concerning them are necessary.

This is one of those Classes abolished by the:cele-
brated Thunberg, and by several less intelligent writers
who have followed him. The reasons which led to
this measure appear to have been, that. Linnzeus has
erroneously placed in Gynandria several plants which
have not the requisite character; hence that character
itself has been judged ambiguous, or not founded in
nature, and the system has been supposed to be sim-
plified by overlooking it. This appears to me a great
mistake. The character of the Class, taken as above,
is as evident, constant and genuine as that of any other
in the system. No doubt can arise, if we be careful
to observe that the stamens actually grow out of the
germen or style, and not merely. out of any part that
supports the germen ; as will appear by examples.

1. Monandria. Stamen, or sessile Anther, one only.

This contains all the beautiful and curious natural
family of the Orchidee, or Orchis tribe, except only

GYNANDRIA. 349

Cypripedium, which belongs to the next Order. I
am induced to consider the bulk of this family as
monandrous, upon a careful review of Professor
Swartz’s representation of the subject, in his excel-
_ lent treatise, just come to my hands in English. See
Tracts relative to Botany translated from different
Languages (by Mr. Konig), printed for Phillips
and Fardon, 1805. I have already, p. 207, men-
tioned the glutinous nature of the pollen of these
plants. This forms yellow elastic masses,. often
stalked, in each cell of the anther, and the cells are
either parallel and close together, or removed from
each other to the opposite sides of the style: which
serves to connect them, just as the filament does in
many Scitamineous plants, alike therefore decided
to be monandrous. Such a decision with regard to
those also is justified by the analogy of other species,
whose cells being approximated or conjoined, pro-
perly constitute but one anther. The grand and ab-
solute subdivision of the Orchidee is justly founded
by Dr. Swartz, after Haller, on the structure of the
anther, whether it be, as just described, parallel,
like that of Orchis, Engl. Bot. t. 22; Ophrys,
¢.65; and Diuris, Evot. Bot. t. 9, &c.; or ver-
tical, consisting of a moveable lid on the top of the
_ style, like Dendrobium, t. 10O—12 ; or Malazis,

Engl. Bot. t.72. The style of the Orchidee has
been called a column, but I think that term now
altogether superfluous. It is really a style, and the

350 GYNANDRIA.

stigma 1s a moist shining space, generally concaye,
and situated, for the most part, in front of the style
beneath the anther. In Orchis bifolia, t. 22,. and
others, it is just above the orifice of the spur. Con-
cerning the nectary of these plants there has been
much diversity of opinion. _ The calcar, spur, in
Orchis, and some other genera, is acknowledged to
be such, and holds abundance of honey. This spur
is judged by Swartz, as well as Linneus, a decisive
generic mark of distinction, and it commonly is so;
but some Indian species brought by Dr. Buchanan
prove it not to be absolute. The remarkable and
often highly ornamented lip, considered by Swartz
as the only corolla, for he takes all the other leaves
of the flower for a calyx, has, by Linnzus and
others, been thought, either a part of the nectary,
or, where no spur is present, the only nectary. Nor
is this opinion so ill-founded as many botanists sup-
pose; for the front of the hp evidently seeretes
honey in Ophrys (or Epipactis) ovata, t. 1548, and
probably in others not yet attended to. Never-
theless, this lip might, like the petals of lilies, be
deemed a nectariferous corolla, were it certain that
all the other leaves were truly a calyx. But the
two inner are so remarkably different from the three
outer ones in Ophrys, t. 64, 65, 71, 383, andabove
all in Stelis, E.vot. Bot. t.75,. that 1am most in-
clined. to take the former for the corolla, the latter
being, according to all appearance, a calyx. An

GYNANDRIA. 3451

insensible gradation from one to the other, of which
we have pointed out other instances in treating of
this subject already, occurs in Diuris, ¢. 8,9; while
in some Orchidee the leaves all partake more of
the habit of a calyx, and in others of a corolla.
Even the lip in Thelymitra, t. 29, assumes. the
exact form, colour, and texture, of the rest of the
flower ; which proves that a dissimilarity between
any of these parts is not always to be expected in
the family under consideration. Vahl appears by
the preface to his Lnumeratio Plantarum to have
removed the Scitaminee to Gynandria, because the
stamen of Canna adheres tothe style. This, if
constant, could only concern that genus, for the
rest of the Order are in no sense gynandrous.

» Diandria. To this Order Cypripedium, Engl.
Bot. ¢t. 1, must be referred, having a pair of very
distinct double-celled anthers. See Zr. of Linn.
Soc. v. 1. t. 2, 3. Here we find Forstera, so well
illustrated by Professor Swartz in Sims.and Konig’s
Annals of Botany, 0. 1. 291, t.6; of which genus
Phyllachne, t. 5 of the same volume, is justly. there
reckoned a species. Of the same natural order with
Forstera is. Stylidium; but. that having, I think,
four anthers, belongs to the fourth Order of the
present Class. Gunnera, placed by Linneus. in
Gynandria_ Diandria, is not yet sufficiently well
understood. |

G52 GYNANDRIA.

3. Triandria. Salacia, if Linnzus’s description be
right, is properly placed here; but Jussieu doubts
it, nor does my dried specimen serve to remove the
uncertainty. Stzlago proves to be merely the bar-
ren plant of Antidesma aleviteria, and belongs to
Dioecia ; as Sisyrinchium and Ferraria do to
Monadelphia, the tubular united stamens of the two
last having been mistaken for a solid style. ARho-

- pium of Schreber (Meborea of Aublet, t.323,)seems
therefore the only certain genus of the Order under
consideration ; unless Lamarck be right in referring
to it Jacquin’s Strumpfia, upon which I have not
materials to form any opinion. ‘The original dis-
coverer attributes to this plant five stamens with
united anthers; hence it found a place in the Syn-
genesia Monogamia of Linneus. Lamarck merits
attention, as he appears to have had an authentic
specimen. See his ¢.731.—

4. Tetrandria. Nepenthes, of whose extraordinary
kind of leaf mention is made p. 150, is the only
genus of this Order in Linnzus, but very erroneously
placed here, for it belongs to Dioecia Monadelphia.
The Order however must be retained for the sake
of Stylidium, a New Holland genus, related, as
above mentioned, to Forstera. ‘This is my Vente-

~~ natia, Exot. Bot. t. 66,67; but another genus
having previously, without my knowledge, received
the latter denomination, that of Stylidium, under

GYNANDRIA. 353

which I had, some time ago, communicated this
genus to the French botanists*, and which they
have adopted, becomes established. See Labillar-
diere’s excellent work on New Holland plants,
where several species of it are figured.

5. Pentandria.4The original genera of this Order,
_ Ayenia, Gluta, and Passiflora, Exot. Bot. t. 28,.
most unquestionably have nothing to do with it,
their stamens being inserted below the germen,,.
merely on a columnar receptacle. The learned.
Schreber therefore removed them to the fifth Class.
It has been thought that this Order might receive’
a reinforcement from the Linnean Pentandria
Digynia. Several of the Contorte have long been
suspected to belong to Gynandria; see Pergularia,.
Ic. Pict. t. 16, and Andr. Repos. t. 184. In this:
genus, as well as Cynanchum and Asclepias, the
pollen appears in five pair of glutinous masses, ex-
actly like the pollen of Orchidea, sticking upon the
stigma. Each mass of pollen is received into a bag,
or cell, formed by a valvular apparatus that encircles
the organs of impregnation, like the generality of
_stamens. ‘The pollen however is, in the above

* T was not aware of Loureiro’s Stylidium, a plant, according to his
description, of the seventh Class: FV. Cochinch. v. 1. 221; but this
can scarcely interfere with ours, being probably, as it grows about Can-
ton, some well-known shrub that happened to have aseven-cleft flower.
It should seem to belong to the Rubiacea, notwithstanding some points
in the description.

QA

354 GYNANDRIA.

genera, not found attached to these cells or valves,
‘but to five glands, each of which is double, and all
of them seated on that thick abrupt angular body
which acts as a stigma*. Nor fs it worth while to
dispute whether this whole body be a stigma or not,
with regard to the question under consideration ; for
it is borne by the styles, above the germen, and
itself bears the anthers. I humbly conceive, haw-
ever, with Linneus and Jacquin, that as part of it,
at least, receives the pollen, stigma is full as good a
‘name for this body as Haller’s term dolium, a tub!
~ Still less is it worth while to controvert with Kolreuter
the propriety of the term pollen, because the sub-
stance in question is not actually a dry powder, any
more than in the Orchis tribe, or in Mirabilis,
Exot. Bot. t. 93. That term is technically used for
the matter which renders the seeds fertile, including
its vehicle, whether the latter be capsular or glu-
tinous, in short, whatever the appearance or texture
of the whole may be. Another question remains,
- more immediately to our present purpose, whether
these plants have five stamens or ten? Jacquin, who
has well illustrated several of them in his Miscell.
Austr. v. 1. t. 1—4, and Rottboll in a dissertation
on. the subject, contend for the latter. Rottboll

I Mr R. Brown believes the cells secrete the pollen, and deposit it
on the stigma, as the pollen of some Orchidee sticks to any part of the
plant. I now readily assent to this, and therefore these plants. must
remain in Pentandria. .

GYNANDRIA. 855

wrote to Haller, that ‘ finding Linnzus deaf to all
‘that had been said, he sent him his treatise, to see
whether he would persist in falsifying nature.” ‘Thus
sordid underlings foment the amimosities and flatter
the failings of their superiors! Linnzus judiciously
suspended his opinion, and, after all, proves to be
most correct. The analogies of the Orchidee and
Scitaminee very clearly decide that the two cells,
or the double masses of naked pollen, can only be
considered as one anther of two lobes. Periploca
greca confirms this. Each lobe of its anthers
stands, as in many Scitaminee, on the outermost
edge of the filament; thus meeting that on the ad-
joining filament, and in appearance constituting with
it atwo-lobed anther, as the lobe of the Scitaminee,
where there is but one filament, meets its corre-
sponding lobe by embracing the style.

6. Hevandria. Aristolochia, Engl. Bot. t. 398, a

~ curious genus, of which there are many exotic spe-

cies, is the only example of this, Péstia being re-
moved to Monadelphia Octandria.

7. Octandria. The, Scopolia of Linneus, which
originally constituted. this Order, proves to be a
Daphne; see Plant. Ic. ex Herb. Linn. t. 34.
Cytinus however, Cavan. Ic. t.. 171, a singular

.) parasitical plant on the roots of Cistus in the south
of Europe, has properly been brought hither from
the Order Dodecandria, of which it originally

DQAQ

~ ad.

356 GYNANDRIA.

formed the only example. The observations of
Dr. Sibthorp and Mr. Ferd. Bauer confirm those of
other botanists, that the anthers are eight, | not six-
teen, and that they are truly inserted upon the style.

8. Decandria is now abolished. Of the two genera
which constituted it, K/einhovia belongs to the Class
Dodecandria, having fifteen stamens, see Cavan.
Monadelph. t. 146; and sein iioe to aaa ae
Monogynia. .

9. Dodecandria is Hilvons tars abolished.

10. Polyandria is in a similar predicament, fo —
not aware of any genus that can be adinitted into it.
Xylopia goes with the greatest propriety to its na-
tural allies in Polyandria Polygynia, Annona; &c.,
its short stamens being inserted into the receptacle
below the germen. Grewia, as well as Schreber’s
Mucrocos, a good genus, belong to Polyandria Mo-
nogynia, the organs of: impregnation being merely
elevated ona common stalk, like those of Passi ora
and Ayenia. Ambrosinia, Arum, and Calla, are
all justly removed by Schreber to Monoecia, though
I think, for reasons hereafter given, they are more
commodiously and naturally placed in the Order
Polyandria of that Class, than in the Order Mo-
nandria. Dracontium and Pothos, of the’ same —
natural family, having perfect or united flowers, the
former with seven stamens to each, the latter with
four, are undoubtedly to be referred to theircorre-

MONOECIA. 357

~ sponding Classes. Heptandria and Tetrandria.

_ Zostera, the only remaining genus of Gynandria
Polyandria in Linneeus, I have iong ago ventured
to remove to Monandria Monogynia;-see Engl.
Bot. t. 467.

Crass 21. Monoecia. Stamens and Pistils in separate
flowers, but both growing on the same individual
plant. Orders 9 or 10.

Several reformers of the Linnzan system have also
abolished this Class and the two following, by way of
rendering that system more simple. Ten years’ addi-
tional experience since the preface to the seventh
volume of Hnglish Botany was written, have but con-
firmed my opinion, there given, on this subject. If
any plants ought to be removed from these Classes,
they must be such as have the structure of all the
accessory partsof the flower exactly alike, (the essential
parts, or stamens and pistils only, differing,) in both
barren and fertile flowers ; and especially such as have
in one flower perfect organs of one kind, accompanied
by rudiments of the other kind, for these rudiments
are liable occasionally to become perfect. By this
means dioecious species of a genus, as in Lychnis,
Valeriana, Rumev, &c., would no longer be a re-
proach or inconvenience to the system. But, on the
other hand, some difficulty would occasionally arise to
a student, in deciding whether there were any real
difference of structure between these accessory partsor

358 _ MONOECTIA.

not, and it might puzzle an adept to determine the
question. For instance, whether the nectary in Salix,
different in the barren and fertile | flowers of some
species, should lead us to keep that genus in, Dioecia,
though in other species the nectary is precisely alike in
both the kinds, and occasionally an abortive germen
occurs in the barren flowers, as stamens do, more
rarely, in some fertile ones. Considering all this, I
should refer Salix to Diandria Monogynia.

With respect to those Monoecious. or Dioecious
genera whose barren flowers are decidedly unlike the
fertile ones, the former being in a catkin, the latter.
not, «as Corylus, Quercus, &e., I conceive nothing
more pernicious or troublesome can be attempted than
to remove them to the Classes of united flowers. They
meet with no allies there, but, on the contrary, form
- so natural an assemblage by themselves, as to be una-
nimously kept separate by the authors of every natural
system that has appeared. But even if this were not
the case, there is a most important reason for keeping
them as they are, which regards the artificial system
more particularly, and of which its author was well
aware; they are of all plants most uncertain in the
number of their stamens. Now this uncertainty is of
little moment, when we have them primarily distin+
guished and set apart from other plants by their Mo-
noe¢ious or Dioecious character; because the genera
being few, and the Orders. constructed widely as to
number of Stamens, we find little difficulty in deter-

oe

MONOECIA. 359

mining any genus, which would be by no means. the
case if we had-them confounded. with the mass of the
system. Even the species of the same genus, as: well
as individuals of each species, differ among themselves.
How unwise and unscientific then is it, to take asa
primary mark of discrimination, what nature has evi-
dently made of less consequence here than in any
other case! Itis somewhat like attempting a natural
system, and founding its primary divisions on the
artificial circumstance of number of stamens.

{ proceed to give some illustrations of the Orders
in Monoecia.

1. Monandria. Zannichellia, Mill. Illustr. t.77, and
Aegopricon, Plant. Ic. ev Herb. Linn. t. 42, are
genuine examples of this Class and Order, having
a diflerent structure in the accessory parts of their
barren and fertile flowers. Artocarpus, the cele-

brated Bread-iruit, may likewise be esteemed so on
account of a partial calyx in the barren flowers.
The other amentaceous genera may most intelligibly
perhaps be referred to the Order Polyandria. Chara
is now removed to the first Class in the System ;
see Mngl. Bot. t. 3306.

2. Diandria. Anguria can remain here only till the
proposed reformation takes place, having no diffe-
rence of structure in its flowers. Lemna, so imper-
fectly known when Linneus wrote, is now well

360 MONOECIA.

understood, and, having frequently united flowers,
belongs to the second Class; see Engl. Bot. t. 926,
1095,.12353.

3. Triandria. 'The great genus of Carex, ¢t. 1051,
928, 993—995, &c., and some other grassy plants,
are found here. Typha, t. 1455—1457, 1s less
clear in its structure; Sparganium, t. 744, 745,
273, is sufficiently so. Tragia, Hernandia and
Phyllanthus are properly placed in this Class and
Order.

4. Tetrandria. Littorella, t. 468 ; the valuable genera
Betula, t. 1508, and Buus, t. 1341; also the
Nettle Urtica, t. 1236; are good examples of this.
Morus the Mulberry, of the same natural order as
the Nettle, has scarcely any difference of structure

“in the accessory organs of the flowers. ‘This tree,
however, is remarkable for being often inclined to
become even dioecious in its constitution, one indi-
vidual bearing most fruit when accompanied by an-
other whose barren flowers are more effective than
its own. Empleurum, Evot. Bot. t. 63, is one of
those ambiguous genera which are but imperfectly
monoecious. . |

5. Pentandria. Xanthium, Ambrosia,. Nephelium,
Parthenium, Iva and Clibadium all partake, more
or less accurately, of the nature of compound
flowers; but their anthers not being united, they

MONOECIA. 361.

- could hardly be referred to the Class Syngenesia*

- particularly Xanthiwn and Nephelium, whose fer-
tile flowers have no resemblance to that Class.

| Amaranthus, an extensive dung-hill genus in warn
countries, analogous to our Chenopodium, follows
next. Leea is the same with Aquilicia, and belongs
to Pentandria Monogynia, the former name being
retained for the sake of the highly meritorious bo-
tanist.and cultivator whom it commemorates. The
Gourd tribe, Cucurbita, Cucumis, Bryonia, Engl.
Bot. t. 439, might be brought hither from the
abolished Order Syngenesia, unless it should be
thought better to consider them as polyadelphous,
to which I am most inclined.

6. Hevandria. Zizania, Tr. of Linn. Soc. 0.7. t. 13;
and Pharus, Browne's Jamaica, t. 38, both grasses,
compose this Order, to which Schreber has added
Epibaterium and Pometia of Forster, as well as
the splendid Guettarda, Hort. Mal. 0.4. t. 48. —

~The latter varies from six to nine in the parts of the
flower, and constitutes the Order Heptandria in
Linneus, according to his usual principle, of placing
such irregular plants, as much as possible, in small
Classes or Orders, that they might be the more
easily found.

7. Polyandria. Stamens more than seven. Cerato-

* Willdenow however has removed Iva and Parthenium thither, ac-
cording to the original ideas of Linneus, in Gen. Pl. ed. 1.

362 - MONOECTA.

phyllum, Engl. Bot. t. 947, 679; Myriophyllun,
t. 83,218; and the handsome Sagittaria, t..84,
stand here at present, but the “accessory parts \in
their two kinds of flowers are alike. Begonia,
- Exot. Bot. t. 101, has the number of its petals,
though various in several species, always sufficiently
different in the barren and fertile flowers. to. fix it
here.—The most indubitable plants of this Order
are amentaceous, Quercus, Lngl. Bot. t. 1342 ;
Fagus, t: 886; Corylus, t.723; Carpinus, Ju-
glans, Platanus, &c.— Arum, t. 1298, Calla.and
Ambrosinia, all brought hither from the twentieth
Class, seem to me perfectly intelligible as simple
monoecious flowers, the barren one, with many
stamens, being superior, or interior, with respect to
the fertile, like the generality of monoecious, as
well as all compound flowers, and not inferior, ‘i
as in every nae one, erterior.

8, Monadelbhae The Fir, Pinus, so magnificently
illustrated by Mr. Lambert, is very distinct in its two
kinds of flowers. Each barren one consists of a
naked tuft of monadelphous stamens, accompanied
only by a few bracteas at the base. The fertile ones
are catkins, with similar bracteas, each scale bearing
on its upper side a pair of winged seeds, and on its”
under a leaf-like style and acute stigma ; as Jussiew
first, rightly I believe, suggested, though some bota-
nists have understood these parts otherwise. Aca-

MONOECIA. 363

lypha, Croton, Jatropha, Ricinus, and several others
of the natural order of Euphorbia, acrid milky
plants, form a conspicuous and legitimate part of
Monoecia Monadelphia. _Omphalea is justly asso-
ciated with them by Schreber, though placed’ by
Linneus in the Order 7riandria, and this alteration

_is the more fortunate, as one of its species is dian-
drous. Sterculia is best removed to fhie eleventh
Class, next to. Kleinhovia.

9. Polyadelphia. If the system should be preserved
in its present state, without regard to agreement or
difference in the accessory parts of the barren and
fertile flowers, I conceive this Order might be esta-
blished for the reception of the Gourd tribe, as
already hinted under the fifth Order. ‘Their fila-
ments are united, in three sets, a character much
more intelligible and constant than the casual and
irregular connexion of their anthers, which led Lin-
nus to reckon them syngenesious ; for they only
afford an additional proof that union of anthers is,
in simple flowers, neither a good natural nor arti-
ficial. guide. If the monoecious and_ dioecious
Classes be reformed according to the plan to which
I have so often adverted, these plants should go to
the Class Polyadelphia.

10. Gynandria is scarcely tenable, being paradoxical
in its character, and the two Linnzan genera which
compose it, Andrachne and Agyneia, seem most

364 DIOECIA.

properly, even as the system stands at present, to
belong to the eighth Order, to great part of which
they are, moreover, naturally related.

Crass 22. Dioecia.. Stamens and Pistils in separate
flowers, situated on two separate plants. Orders 8.

The foregoing remarks on the Orders of Monoecia
apply also to those of this Class. I shall therefore only
briefly mention some genera properly illustrative of
each Order, more particularly specifying such as re-,
quire to be placed elsewhere. |

1. Monandria. Brosimum of Swartz, and Ascarina
of Forster, seem, by their descriptions, to be well
placed here. Pandanus (Athrodactylis of Forster)
is more doubtful, not having any partial calyx or
corolla to divide the stamensinto separate blossoins,
so that the whole may be taken either for a polyan-
drous or a monadelphous flower, as well as for an
assemblage of monandrous ones. Najas is a good .
and immutable example of this Order. Of Thun--
bere’s Phelypea I have not materials to form a
judgement.

2. Diandria. The wonderful Valisneria, Jacq. Eclog.
ft. 1. already described p. 255, is a decisive example
of this. Cecropia also seems unexceptionable. Of
Salix, see Engl. Bot. 0.20 and @1, &c., I have al-
ready spoken, p. 353. The scales of its barren and
fertile catkins are alike: its nectaries various. -

DIOECIA. 365

3. Triandria. Elegia and Restio, hard rushy plants,
chiefly of the Cape of Good Hope and New Hol-
land, appear to be without any difference in the
accessory parts of their flowers, which is certainly
the case with Empetrum, Engl. Bot. t.526, Ruscus,
¢. 560, brought hither from Dioecia Syngenesia,
Osyris, Excecaria and Maba; Caturus only seem-
ing differently constructed in this particular; but I
have not been able to examine the three last.

4, Tetrandria. Trophis, Batis,and Hippophae, t. 425,
_ are good examples of this, though Mr. Viborg is
recorded by Schreber to have occasionally found
united flowers, intermixed with the barren ones, in
the last-mentioned genus. If this be usual, Hip-
pophae must be removed to Polygamia Dioecia.
The rest of the Order appear to have the accessory
parts alike in both flowers, as Viscum, ¢. 1470.

5. Pentandria. Humulus, t. 427, is almost the only
certain instance here. Spinacia, Acnida and Can-
nabis would be unexceptionable, but they are less
absolutely dioecious, being sometimes monoecious ;
see p.252. The rest of the Order is at best doubt-
ful; nor can the pretended amentum of the barren-
~~ flowered Pistacia entitle it to a permanent place in
this Class, for its fructification is truly a panicle.
Clutia, more properly Cluytia, may possibly remain
here. It has no right to a place in the Order
Gynandria. .

366 DIOECIA.

6.

Hevandria. No difference of structure is discernible

between the barren and fertile flowers of any genus

8.

in this Order; witness Zamus, t..91, though some-

‘thing to the contrary is mentioned in the Genera

Plantarum of Linneeus.

Polyandria. Under this Order I would certainly
comprehend all dioecious plants that have from
eight to any greater number of stamens, according
to the example set by Linneus himself in the last
Class. ‘The genera are exceedingly variable in this
respect; and if all those, the accessory parts of
whose flowers are uniform, were taken away, ‘the
remainder would be so few, that it is hard to’say
whether any would remain at all. Instances of the
Order-as it now stands are Populus, t. 1618, 1619;
Hydrocharis, t. 808; Mercurialis, t. 559. The
fertile flowers of the latter have, in some cases, a
nectary or, corolla of two slender leaves, not found
in the barren ones, which may entitle it to a perma-
nent place here. Carica will also probably remain.
Rhodiola can scarcely be kept distinct from Sedum.
Coriaria and Ailanthus, having often united flowers,
are best in the tenth Class, as Euclea in the eleventh.
I find no genera truly icosandrous_ here, though
Schreber esteems oi lacourtia and Hed, lycarya to
be so,

Monadelphia. Taxus, t. 746, and perhaps Juni-
perus, t. 1100, also the exotic Ephedra, are legiti-

POLYGAMIA. 367

«mate examples of this order. Spurious ones are
Nepenthes, Myristica the Nutmeg, and Schreber's
Xanthe, all placed by him in the now abolished
Order Syngenesia, and which can only take shelter
here while the Class remains as it is, for they have
no difference of structure in the accessory parts of
their flowers.

Crass 23. Polygamia. Stamens and Pistils separate
in some flowers, united in others, either on the same
plant or on two or three distinct ones; such diffe-
rence in the essential organs being moreover accom-
panied with a diversity in the.accessory parts of he *
flowers. Orders 3.

1. Monoecia. United flowers accompanied with barren
or fertile, or both, all on one plant. Atriplex,
Engl. Bot. t. 261, 232, &c., is an instance of this,
having the barren flowers of five regular spreading

‘segments, the united ones of two compressed valves,
which, becoming greatly enlarged, protect the seed.
In several species however the flowers are none of
them united, each having only stamens or only
pistils. Throughout the rest of the Order, as it
stands in Linneus and Schreber, I can find no
genus that has the requisite character. Some of the
grasses indeed have awns to one kind of flower only,
but that part is too uncertain to establish a character
upon; and this family is so natural in itself, and so
liable to variations in the perfecting of its flowers or

368 POLYGAMIA.

florets, that there can be no doubt of the propriety
of classing its genera simply by the number of their
stamens and styles, which are very constant.

2. Dioecia. The different flowers on two different
plants. I can scarcely find a certain instance of
this, except Hippophae, already mentioned. under
Monoecia Tetrandria.

3. Trioecia. Of the only two genera which have —
ever been placed here, Ceratonia, Cavan. Ic. t. 113,
belongs to Pentandria Monogynia. Ficus is so
celebrated for the diversity of its flowers, as con-
nected with the history of vegetable impregnation,
see p. 256, that we are glad to take advantage ofa
trifling difference in the calyx of the two florets,
(the barren one being most frequently three-cleft, —
the fertile five-cleft,) to keep it here.

All things being considered, this Class may be
thought scarcely worth retaining. Yet as we know
two or three genera entitled to a place in it, upon
principles which the analogy of the two preceding
‘Classes shows to be sound, we cannot tell but others
may exist in the unexplored parts of the globe. For
this reason, and for the uniformity of the system, I
would venture to preserve it. If the twenty-first and
twenty-second Classes should hereafter be reformed —
by some judicious and experienced hand, according
to the principle I have suggested, of retaining in -
them such genera only as have a permanent diffe-

CRYPTOGAMIA. 369

rence in the accessory, as vell as the essential,
parts of their flowers, their bulk being by such a
reformation much diminished, it might be advisable
to reduce them to one Class, in which the slender
remains of Polygamia might commodiously be in-
cluded, and the title of such a Class should be
Diclima, expressing the two distinct seats, or sta-
tions, of the organs of fructitication.

Cuiass 24. Cryptogamia. Stamens and Pistils either
not well ascertained, or not to be numbered with
any certainty. Orders 5.

. Filices. Ferns. The parts of their flowers are
almost entirely unknown. ‘The fructification, taken
collectively, and proved to be such by the produc-
tion of prolific seeds, grows either on the back,
summit, or near the base of the frond. Some are
called annulate, annulated, their capsules being
bound with an elastic transverse ring; others thecate,
or more properly exvannulata, from the want of
such an appendage, of which some of the latter
have, nevertheless, a spurious vestige. All the
former, and some of the latter, are dorsiferous,
bearing fruit on the back of the frond, and of these
the fructification is either naked, or else covered
with a membranous involucrum. The genera are
distinguished by Linneus according to the shape
and situation of the spots, or assemblages of cap
sules, besides which I have first found it necessary

2B

-

370 CRYPTOGAMIA.

to take into consideration the absence or presence
of the involucrum, and especially the direction in
which it bursts. See T'racts relating to Nat. Hist.
215, t. 1. |

Polypodium, Engl. Bot. t. 1149, has no invo-
lucrum ; Aspidium, t. 1458—1461, has a single,
and Scolopendrium, ¢. 1150, a double one. Os- —
munda, t. 209, has been remarked by Professor
Swartz to have a spurious ring. It is one of those
ferns the lobes of whose frond are metamorphosed,
asit were, into spikes of capsules. Botrychium of
Swartz, more distinctly spiked, and having no ves-
tie of a ring, is separated by him from Osmunda.
See one species of itin Engl. Bot. t. 318. Ophio-
glossum, t. 108, and Equisetum, t. 915, 929, are
other examples of spiked ferns. _ Each seed of the —
latter is embraced by four filaments, judged by Hed-
wig to be the stamens. Supposed ferns, with radical
fructifications, ave Pelularia, t. 521, and Lsoetes,
¢. 1084; but the former might pessibly be referred
to Monoecia Polyandria, and the latter to Monoecia
Monandria, as the system at present stands, Lyco-
podium, t.224, 1148, &c., is a fern, at least im my
opinion, with axillary fructification.

. Musci. Mosses. These are really herbs* with di-
stinct leaves and frequently as distincta stem. Their
conical membranous corolla is called a calyptra,

* Hedwig’s term musci frondosi is incorrect. ”

CRYPTOGAMIA. Fe |

Ff. 151, or veil, its summit being the stigma. This
veil clothes the capsule, which, before the seed
ripens, is elevated on a fruit-stalk. The capsule is
of one cell and one valve, opening by a vertical lid,
f-213*. Seeds very numerous and minute. The
barren flowers of mosses consist of an indefinite
number of nearly cylindrical, almost sessile, anthers,
f- 190; the fertile flowers, of one (rarely more)
perfect pistil, accompanied by several barren pistils,
jf- 192. Both stamens and pistils are intermixed
with numerous succulent jointed threads, /. 191,
which perhaps answer the purpose of a calyx or
corolla, as far as protection is concerned. Some
few species of moss have the stamens and pistils |
associated in the same flower, but they are generally
separate. Hypnum, Engl. Bot. t. 1494, 1425, has
a scaly sheath, or pertchetium, f. 150, at the base
of its fruit-stalk, composed of leaves very different
from the foliage of the plant. This is considered as
a sort of calyx, see p. 192, and as such is allowed
to enter into the generic character; but there is
some reason to esteem it rather of the nature of
_ bracteas. The capsule of Splachnum, Engl. Bot.
t. 144, &c., stands on a peculiar fleshy base, called
apophysis, f. 189 a. |

~ Micheli in his Genera Plantarum, published in
1729, tab. 5Y, has well represented the parts above

* This part in Phascum only does not separate from the capsule.

4a
252

Q CRYPTOGAMIA.

described, though he mistook their use, being quite
ignorant of the fecundation of plants. Dillenius
took the one flower precisely for the other, and yet
absurdly called capsula what he believed to be an-
thera. Linneeus, who had previously formed just
ideas on the subject, as apvears from his Tour to
Lapland, too implicitly submitted his own judge-
inent to that of Dillenius, and adopted his hypothe-
sis, at the same time correcting, as he thought, his
phraseology. Hence the whole glare of the blun-
der of Diilenius has fallen on Linneus ; for while
we read, in the Linnzan definitions of mosses, every
where the word anthera, and in those of Dillenius,
usually accompanying therm, capsula ; few persons,
who have lately been instructed by Hedwig that the
part in question is really a capsule, take the trouble
to recollect that Dillenius so grossly misused that
word. Various ideas have been started on this
subject by Haller, Necker, and others, which could
only claim attention while it remained in great ob-
scurity. The excellent Hedwig has entirely the
merit of an original discoverer in this branch of
physiology. He exainined all that had been done
before his time, detected the truth, raised | mosses
from seed, 7: 193—196, and established their cha-
racters on the principles we have already explained.

The Linnean genera of Mosses are chiefly founded
on the situation of the capsule, whether lateral or
terminal, with some other circumstances. ‘They are

CRYPTOGAMIA. Tis

too few, and not strictly natural. Hedwig first
brought into notice the structure of the fringe, peri-
stomium, which in most mosses borders the orifice
of the capsule. This is either simple, f. 189 b, or
double, /. 213, 214, and consists either of separate
teeth, or of a plaited and jagged membrane. The
external fringe is mostly of the former kind, the
- Inner, when present, of the latter. ‘The number of
teeth, remarkably constant in each genus and spe-
cies, is either four, eight, sixteen, thirty-two or sixty-
four. On these therefore Hedwig and his followers
have placed great dependence, only perhaps going
into too great refinements relative to the internal
fringe, which is more difficult to examine, and less
certain, than the outer. Their great error has been
laying down certain principles as absolute in form-
ing genera, without observing whether all such ge-
nera were natural. Such mistakes are very ex-
eusable in persons not conversant with botany ona
general scale, and whose minute and indefatigable
attention to the detail of their subject, more than
compensates the want of what is easily supplied by
more experienced systematics. Thus Barbula of
Hedwig is separated from Tortula, Engl. Bot.
t. 1663, and Fissidens from Dicranum, t. 1272,
1273, on account of a difference ot form or situa-
tion in the barren flowers, which is evidently of no
moment, and merely divides genera that ought to be
united. The same may be said of genera founded

374 CRYPTOGAMIA.

ss)

on the union of the stamens and pistils inone flower.
On this subject I have been more diffuse in a paper
on Mnium, in Tr. of Linn. Soc. v. 7. 254, to

which I beg leave to refer those who are desirous

of studying it further. Various and abundant spe-
cimens of this tribe of plants, showing the various
structure of the fringe, lid and other parts, may be»
seen in the latter volumes of English Botany more
especially.

Mosses are found in the hottest and coldest
climates. They are extremely tenacious of life,
and, after being long dried, easily recover their
health and vigour by moisture. Their beautiful .
structure cannot be too much admired. ‘Their spe-
cies are numerous, and in some cases difficult to
determine, particularly in the genera Tortula and
Orthotrichum; nor is the generic character of the
latter so easy or certain as most others. Schreber,
Dickson, Swartz, Bridel, Weber, Mohr and Turner
are great names in this department of Botany, be-

sides those of whom we have already spoken.

. Hepatice. Liverworts. Of these the herbage is

commonly frondose, the fructification originating
from what is at the same time both leaf and stem.

_ This character, however, proves less absolute than

one founded on their capsules, which differ essen-
tially from those of the preceding Order in having
nothing like a lid or operculwn. ‘The corolla, or

CRYPTOGAMIA. 375

veil, of some of the genera is like that of Mosses,
but usually bursts at the top. The barren flowers in
some are similar to the stamens of the last-mentioned
plants, as in Jungermannia, see Hedwig’s Theorie,
t.16*; in others they are of some peculiar confor-
- mation, asin Marchantia, Engl. Bot. t. 210, where
they are imbedded in a disk like the seeds of Lichens,
in a manner so contrary to all analogy, that bota-
nists can scarcely agree which are the barren and
which the fertile flowers of this genus. The four-
valved capsule of Jungermannia, with the veil burst-.
ing at its summit to let the fruit-stalk pass, may be
seen in Hngl. Bot. t. 185, 186, which are both
frondose species, like J. epiphylla, t.771, whose
calyx as well as corolla is evident; and ¢. 605—
608, which have apparently distinct leaves, like
Mosses, Anthoceros, t. 1537, 1538, is a curious
genus of the Hepatice. Linneus comprehended
this Order under the following one, to which it is,
most assuredly, far Jess akin than to the foregoing.

4, Alge. Flags. In this Order the herbage is fron-
dose, sometimes a mere crust, sometimes of a
leathery or gelatinous texture. - The seeds are im-
bedded, either in the frond itself, or in some pecu-
liar receptacle. ‘The barren flowers are but imper-
fectly known. Here we find that great natural

* See also Mr. W. J. Hooker’s valuable Monograph on Jungerman-

nia, t.13, where the anthers are ascertained to be membranous, dis-
charging the pollen at the apex.

376 CRYPTOGAMIA.

Order, comprehended by Linnaeus under one genus
by the name of Lichen, the fructification of which,
for the most part, consists of a smooth round disk,
f- 198, flat, convex, or concave, with or without an
adventitious border, in the substance of which disk
the seeds are lodged. In some others they are
placed in powdery warts, or in fibrous receptacles.
The barren flowers are supposed, to be powdery
also, f. 197, very much like those of Jungermannia.
See Engl. Bot. ¢t. 126, and various other parts of
that work, where a great number of species are
figured. The whole tribe has been much investi-
gated, and attempted to be divided into natural
genera founded on habit, by Dr. Hoffmann. of
Goettingen, whose figures are perfect in their kind.
But a more complete scheme for reducing this
family to systematic order has been made known
to the world by Dr. Acharius, a learned Swede,
who in his Prodromus, and Methodus Lichenwmn,
has divided it into genera founded on the receptaele
of the seeds alone. Hence those cenera, though
more technical, are less natural than Hoffmann’s ;
but they will, most likely, prove the foundation of
all that can in future be done on the subject, and
the works of Acharius form a new era in crypto-
gamic botany. It is only perhaps to be regretted
that he has been somewhat too prodigal of new
terms, which when not wanted are always a burthen
to science, and rather obscure than illustrate it.

/

CRYPTOGAMIA. 377

Thus Hedwig used the term sporangium for a seed-
vessel, pericarpiuin, i which the learner would
seek in vain for any distinction, or new idea. <A
student might very justly complain if, in a science
necessarily so overburthened with words, he were
required to call the same part by a different name
in every different family. I would giadly therefore
retain the word frons in preference to the thallus
of Acharius, receptaculum for his apothecium, pedi-
cellus for his bacillum or podetium, and semina for
his spore, because I see no improvement in the
change. When this or any other writer strikes out
new ideas, and discriminates parts hitherto mistaken
‘or unknown, we thankfully receive from him new
terms to express his discoveries. Thus the cyphella
ot Acharius is a peculiar sort of pit or pore, on the
under side of the trond, in that section of Lichens
called Séicta, see Engl. Bot. t. 1103, 1104; his
lirelle ave the black letter-like receptacles of the
genus Opegrapha, t. 1753—1750; bis trice the
analogous parts, resembling a coiled horse-hair, in
Gyrophora, the Umbilicaria of Hotimann, 7. 522.
These terms are necessary and instructive, and are
chosen with that accuracy and taste for which Dr.
Acharius is conspicuous.

Vhe aquatic or submersed A/y@ form a distinct
and peculiar tribe. Some of these abound in fresh
water, others in the sea, whence the latter are com-
monly denominated sea-weeds. ‘The chief genera.

378 - CRYPTOGAMIA.

are Uloa, t. 419, 420, 1276, well defined by its
seeds being dispersed under the cuticle throughout
the membranous or gelatinous substance of the
frond; Fucus, t. 1066—1069, &c., whose seeds are
collected together in tubercles or swellings, of va-
rious forms and sizes; and Conferva, of which the
twenty-fourth and. twenty-fifth volumes of Engi.
Bot., more especially, show various specimens. This
last genus is commonly known by its capillary, and,
for the most part, jointed frond. The seeds of some
species are lodged in external capsules or tubercles ;
of others in the joints of the frond; and hence the
ingenious Dr. Roth has formed a genus of the for-
mer, called Ceramium. His Rivularia, Engl. Bot.
_t. 1797—1799, is perhaps more satisfactorily sepa-
rated from Conferva, as we trust is Vaucheria,
t. 1765, 1766, a fresh-water genus named after M@. .
Vaucher of Geneva, who has published an elaborate
and faithful microscopical work on Fresh-water Con-
fervas. The submersed Alge@ in general are merely
fixed by the roots, their nourishment being imbibed
by their surface. Many of them float without being
attached to any thing. The genus Fucus has re-
ceived more botanical attention than the rest of this
tribe; and the works of Gmelin, Esper, Stackhouse
and Velley have ascertained many species, which
the labours of Dr. Goodenough, Mr. Woodward
and Mr. Turner have reduced to systematic order.
Still amore perfect combination of the skill of the

CRYPTOGAMIA. 379

painter and the botanist has long been desired, re-
lative to the genus in question, which is now sup-
plied by the Astoria Fucorum of the writer last
mentioned, and his friend Mr. W. J. Hooker.

. Fungi. Mushrooms. These cannot properly be
said to have any herbage. Their substance is fleshy,
generally of quick growth and short duration, dif-
fering in firmness, from a watery pulp to a leathery

or even woody texture. | By some naturalists they

have been thought of an animal nature, chiefly be-
cause of their foetid scent in decay, and because
little white bodies like eggs are found in them at
that period. But these are truly the eggs of flies,
laid there by the parent insect, and destined to pro-
duce a brood of maggots, to feed:on the decaying
fungus, as on a dead carcase. Ellis’s_ beautiful

_ discoveries, relative to corals and their inhabiting
polypes, led to the strange analogical hypothesis

that these insects formed the fungws, which Mun-
chausen and others have asserted. Some have
thought fungi were composed of the sap of cor-

-rupted wood, transmuted into a new sort of being ;
an idea as unphilosophical as the former, and un-
supported by any semblance of truth.

Dryander, Schefter and Hedwig have, on much
better grounds, asserted their vegetable nature, de-
tected their seeds, and in many cases explained their
parts of fructification. In fact, they propagate their

380 CRY PTOGAMIA.

species as regularly as any other organized beings,
though, like others, subject to varieties. Their se-
questered and obscure habitations, their short du-,
ration, their mutability of form and substance, ren-
der them indeed more difficult of investigation than
common plants, but there is no reason to. suppose
them less perfect, or Jess accurately defined. Splen-
did and accurate works, illustrative of this Order,
have been given to the world by Scheffer, Bulliard
and Sowerby, which are the more useful, as the
generality of fungi cannot well be preserved. The
most distinguished writer upon them, indeed the
only good systematic one, is Persoon, who has
moreover supplied us with some exquisite figures.
His Synopsis Methodica Fungorum helps us to the
following arrangement.

1. Angiocarpi, such as bear seeds internally.
These are either hard, like Spheria, Sowerb. Fung.
t. 159, 160; or membranous, tough and leathery,
like Lycoperdon, t. 331,352; Cyathus ( Nidularia)
¢. 28,29; or Batarrea (Lycoperdon) t. 390.

2. Gymnocarpi, such as bear seeds imbedded in
an appropriate, dilated, exposed membrane, deno-
minated hymenium, like Helvella, t. 39, in which
that part is smooth and even; Boletus, ¢. 34, 87,
134, in which it is porous; and. the vast genus
Agaricus, t. 1, 2, &c.,'in which it consists of pa-
rallel plates called /amelle, or gills.

Persoon has been commendably sparing of new:

PAIM®. 38 }

terms. Besides hymeniwm above explained, he has
scarcely introduced any other than peridium, for the
round membranous dry case of the seeds in some
of the first section. The term pileus, a hat, is used
by all authors for the head of those fung? sive com-
pose the second section.

APPENDIX. Palme. The natural order of Palms
was so little understood when Linneus formed his
systematical arrangement of plants, and so few ot their
flowers had been scientifically examined, that he was
under the necessity of leaving this order as an appendix
to his system, till it could be better investigated. To
its peculiar habit and physiology we have adverted in
several of the foregoing pages, see p. 45, 48, 103, &e.

Late observations show Palms to have for the most
part six stamens, rarely three or nine, with three or six
petals, and one or three styles ; which last are some-
times in the same flower with the stamens, sometimes
im a separate one, but both flowers always agree in
general structure. Their fruit is generally a drupa.
They are akin to the /idiaceous tribe, and Linnzus
happily terms them the princes of the vegetable king-
dom. His most numerous remarks concerning them
occur in his Prelectiones in Ordines Naturales Plan-
tarum, published by Professor Giseke at Hamburgh in
1792, trom private lectures and conversations of Lin-
neus. This work however is necessarily full of errors
and mistakes, not only from its mode of compilation

282 OF MAKING AN

and the intricacy of the subject, but because Linnzus
had only partially studied certain parts of that sub-
ject, and was undecided in his sentiments upon those
parts. It was a singular instance of indulgent liberality
in him to allow his disciples Fabricius and Giseke to
make notes, for their own use, of what he considered
himself as scarcely competent to lay in a finished form
before the public. We are obliged to. the editor-for
preserving these valuable though crude materials, and
he has shown ability in digesting and elucidating them.
I should scarcely, for my own part, have thought it
right to furnish still more crude and imperfect guesses
and opinions, from manuscripts which their illustrious
author had purposely, as it appears, withheld from his
auditors, lest he should lead them into error. This
will explain a note in Professor Giseke’s preface, p. 19,
which however was printed before his request-came to
my knowledge; for two very intelligent friends, through
whom it was meant to be conveyed, judged it unrea-
sonable to be made, as well as improper to be com-
plied with, and therefore suppressed the message.

I have only to add a few practical remarks on the
preparation and use of an Herbarium or Hortus Siccus.
The advantages of preserving specimens of plants, as
far as it can be done, for examination at all times and
seasons, is abundantly obvious. Notwithstanding the

HERBARIUM. 383

multitude of books filled with descriptions and figures
of plants, and however ample or perfect such may be,
they can teach no more than their authors observed ;
but when we have the works of Nature before us, we
can investigate them for ourselves, pursuing any train
of inquiry to its utmost extent, nor are we liable to be
misled by the errors or misconceptions of others. A
good practical botanist must be educated among the
wild scenes of nature, while a finished theoretical one
requires the additional assistance of gardens and books,
to which must be superadded the frequent use of a
good herbarium. When plants are well dried, the
original forms and) positions of even their minutest
parts, though not their colours, may at any time be
restored by immersion in hot water. By this means
the productions of the most distant and various coun-
tries, such as no garden could possibly supply, are
brought together at once under our eyes, at any season
of the year. If these be assisted with drawings and
descriptions, nothing less than an actual survey of the
whole vegetable world in a state of nature, could
excel such a store of information.

Some persons ¥ ecommend the pr samttecioat speci-
mens in weak spirits of wine, and this mode is by far
the most eligible for such as are very juicy. But it
totally destroys their colours, and often renders their
parts less fit for examination than the above-mentioned
mode. It is besides incommodious for frequent study,

S84 OF MAKING AN HERBARIUM.

and a very expensive and bulky way of making an
herbarium. |

The greater part of plants dry with facility between
the leaves of books, or other paper, the smoother the
better. If there be plenty of paper, they often dry
best without shifting ; but if the specimens are crowded,
they must be taken out frequently, and the paper dried
before they are replaced. The great point to be at-
tended to is that the process should meet with no
check. Several vegetables are so tenacious of their
vital principle, that they will grow between papers, the
consequence of which is a destruction of their proper
habit and colours. Itis necessary to destroy the life of
such, either by immersion in boiling water, or by the
application of a hot iron, such as is used for linen,
after which they are easily dried. I cannot however
approve of the practice of applying such an iron, as
some persons do, with great labour and perseverance,
till the plants are quite dry, and all their parts incorpo-
rated intoasmooth flat mass. This renders them unfit
for subsequent examination, and destroys their natural
habit, the most important thing to be preserved. Even
in spreading plants between papers, we should refrain
from that precise and artificial disposition of their
branches, leaves, and other parts which takes away
from their natural aspect, except for the purpose of
displaying the internal parts of some one or two of
their flowers, for ready observation.

PRESERVATION OF AN HERBARIUM. $85

After all we can do, plants dry very variously.
The blue colours of their flowers generally fade, nor
~ are reds always permanent. Yellows are much more
so, but very few white flowers retain their natural
aspect. The Snowdrop and Parnassia, if well dried,
continue white. Some greens are much more perma-
~ nent than others; for there are some natural families
whose leaves as well as flowers turn almost black by
drying, as Melampyrum, Bartsia, and their allies,
~ several Willows, and most of the Orchidee. The
Heaths and Firs in general cast off their leaves between
papers, which appears to be an effort of the living
principle, for it is prevented by immersion of the fresh
specimen in boiling water. Nandina domestica, a
Japanese shrub, lately introduced among us by Lady
A. Hume and Mr. Evans of Stepney, is very remark-
able in this respect. Every leaflet of its very compound
leaves separates from its stalk in drying, and even
those stalks all fall to pieces at their joints.

Dried specimens are best preserved by being fast-
ened, with weak carpenter’s glue, to paper, so that
they may be turned over without damage. Thick and
heayy stalks require the additional support of a few
‘transverse strips of paper, to bind them more firmly
down. A half sheet of a convenient folio size, should
be allotted to each species, and all the species of a—
genus may be placed in one or more whole sheets.
On the latter the name of the genus should externally
be written, while the name of every species, with its

2C

386 PRESERVATION OF

place of growth, time.of gathering, the finder’s name,
or any other concise piece ef information, may be in-
scribed on its appropriate paper. This is the plan.of
the Linnean Herbarium, in which every species, which
its original possessor had before him when he wrote
his great work the Species Plantarum, is numbered
both in pencil and in ink, as well.as named, the former
kind of numbers having been temporary till the book
to which they reter was printed, after which they were
confirmed with a pen, and a copy of the book, now
also in my hands, was marked in. reference to them. |
Here therefore we do not depend on the opinion
merely, even of Linnzus, for we have always before
our eyes the very object which was under his inspec-
tion. We have similar indications of the plants de-
scribed in his subsequent works, the herbarium being
most defective in those of his second antissa, his
least accurate publication. We often find remarks
there, made from specimens acquired after the Species
Plantarum was published. These the herbarium oc-
casionally shows to be of a different species from the
original one, and it thus enables us to correct such
errors. fi ag | 5 ane:
_ The specimens thus. pasted, are conveniently kept
in lockers, or on the shelves of a proper cabinet, Lin-
neus in the Philosophia Botanica exhibits a figure of
one, divided into appropriate spaces for each class,
which he supposed would hold his whole collection.
But he lived to fill two more of equal size,:and his

AN HERBARIUM. 387

herbarium*has' been perhaps doubled since his death
by the acquisitions of his son:and of its present pos-
sessor. :

/One'great and mortifying impediment to the perfect
preservation of an herbarium arises from theattacks of
‘insects. A little beetle called Ptinus «Fur is, more
especially, the pest of collectors, laying its eggs in the
“germens or receptacles of flowers, and others of the
more/solid parts, which are speedily devoured by the
maggots when hatched, and by their devastations
_ paper and plants are alike involved in ruin. The most
bitter and acrid tribes, as Euphorbia, Gentiana,
Prunus, the Syngenesious class, and especially Wil-
lows, are preferred by these vermin. ‘The last-men-
tioned family can scarcely be thoroughly dried before
it is devoured. Ferns are scarcely ever attacked, and
grasses but seldom.—To remedy this inconvenience I
have found a solution of corrosive sublimate of mer-
cury in rectified spirits of wine, about two drams to a
pint, with a little camphor, perfectly efficacious. It is
easily applied with a camel-hair pencil when the spe-
cimens are perfectly dry, not before; and if they are
not too tender, it is best done before they are pasted,
as the spirit extracts a yellow dye from many plants,
and stains the paper. A few drops of this solution
should be mixed with the glue used for pasting. This
application not only destroys or keeps off all vermin,
but it greatly revives the colours of most plants, giving
_ the collection a most pleasing air of freshness and
2c

388 PRESERVATION OF AN HERBARIUM.

neatness. After several years’ experience, I can find
no inconvenience from it whatever, nor do I see that
any dried plants can long be preserved without it.
The herbarium is best kept in a dry room without
a constant fire. Linnzus had a stone building for his
museum, remote from his dwelling-house, into which,
I have been told, neither fire nor candle was ever ad-
mitted, yet nothing can be more free than his collec-
tion from the injuries of dampness, or other causes of
decay.

389

EXPLANATION or tue PLATES.

Tas. 1. jig. 1. Anatomy of wood, after Mirbel. See
p.10. f.2. Embryo of Pinus Cembra, shown ina
section of the seed, then separate, and magnified,
from Mr. Lambert's work. See p. 75, 287—289.
f. 3. Seedling plant of the Dombeya, or Norfolk
Island Pine, with its four cotyledons, and young
leafy branches, of the natural size, p.76. f/4.A
garden bean, Vicia Faba, laid open, showing its
two cotyledons, p.74; f the radicle, or young root,
p-73; g the germ or corculum, p.74. Above is
a bean which has made some progress in vegeta-
tion, showing the descending root, the ascending
plumula, p.75, and the skin of the seed Surshnig
irregularly, p. 295.

Tas. 2. Roots. (f. 5. Fibrous, in Grass, p. 81.
f. 6. Creeping, Mint, p. 82. f. 7. Spindle-

_ shaped, Radish, accompanied by its cotyledons and
young leaves, p. 82. f. 8. Abrupt, Scadbiosa —
succisa: f.9. Tuberous, Potatoe, p. 83. f- 10.
Oval knobs of some Orchidee: f.11. Palmate
ones of others: _f. 12. Several pairs of knobs in
Satyrium albidum: p.84. f.13. Solid Bulb in
Crocus: f. 14. Tunicate Bulb in Allium : f. 15.
Scaly one in Lilium: p. 86. f- 16,. Granulated
Root of Savifraga granulata, p. 87.

390 EXPLANATION

Tax. 3. Stems and Buds. f. 17. Forked Stem, in
Chlora perfoliata, p. 90. _f..18. Scaly, in Oro-
banche: f. 19. Radicans, or Clinging, in Ivy,
pool. f-20. Twining from left to right, in-Loni-—
cera; Jf. 21. from. right to,left, in Convolvulus,
p- 92... ff. 2%. Sarmentum, a.Runner, in. the
Strawberry, p. 93. f. 23. Caulis determinate ra-
mosusy as in the Azalea family, p..94: fi 24.
Three pair of Buds, in, Lonicera cerulea, p. 104. —
f. 25. Bud of. the. Horse Chesnut, p- 105.

Tas. 4. Leaves. ie 26. Tufted ae pelle. Sf 27.
Imbricated: . f. 28. Decussated: f, 29. Two-.
ranked, Yew: f. 30. Unilateral, p..113. f. 31.
Peltate, Nasturtium, p..115. f..32. Clasping the
stem, p. 113. f.33. Perfoliate: f. 34. Sheathing:
J. 35. Equitant: (f. 36. Decurrent, p,. 116, and —
spinous, p. 124. f. 37. ee Ruscus

be ht pe 116.°

Tan. 5. f. 38. Orbicular, Hedysarum nesiatiieia
peli? f. 39. Roundish, Pyrola: +40! Ovate:
fr41. Obovate + 242. Fliptical or oval... f. 43.
Spatulite, p. 118. f.44. Wedge-shaped :, f. 45.
Lanceolate: /.46. Linear: //47. Needle-shaped: |
f- 48. Triangular, p. 119. f: 49. Quadrangular,
(also abrupt, p. 122), Tulip-tree: f. 50. Deltoid):
J. 51. Rhomboid:: f. 52. Kidney-shaped, p.'119.
Jj. 53. Heart-shaped: ft 54. Gritvensirtdioed a

OF THE PLATES. . tar

J. 55. Arrow-shaped: —_f. 56. | Halbert-shaped,
(also-acute, p. 123), _f. 57. Fiddle-shaped, (also
obtuse, p. 123), Humex pulcher, p. 120. ff. 58.
Runeinate: 7.59. Lyrate: f. 60. Cloven: #61.
Three-lobed, Anemone Hepatica: f.62. Sinuated,

Oak: /. 63. Deeply divided, ay ey p. 121.
f- 64. Laciniated :

Tas. 6. (f. 65. Palmate: f. 66. Pinnatifid: f. 67.
Doubly pinnatifid, p. 129. 7.68. Pectinate : f. 69.
Unequal, Begonia : f. 70. Jagged-pointed, p. 123.
f- 71. Retuse, Rumer digynus: f.72. Emargi-
nate: 7.73. Pointed: (f: 74. Blunt with a small
point, p. 123. f. 75. Sharp-pointed, Ruscus
aculeatus; f. 76. Cirrose: (f. 77. Spinous,
p. 193. f.78. Fringed: f. 79. Toothed: jf. 80.
Serrated: f. 81. es p- 125.

TaB. 7. f. 82. Doubly as well as sharply crenate,
approaching to f. 80: (f. 83. Jagged: ff. 84.
Wavy, Menyanthes nympheoides : f 85. Plaited,
p- 197. f. 86. Undulated: f. 87. Curled, p. 127.
f- 88. Veiny: f. 89. Ribbed: f: 90. Three-

ribbed, p. 128. 291. Three-ribbed at the base:

f-92. Triply-ribbed: — 7. 93. Cylindrical, Con-

‘chium, p.130. f. 94. Semicylindrical: —_f. 95.
Awl-shaped: (f. 96. Doubly tubular, Lobelia
Dortmanna; f.97. Channelled, p. 130. f. 98.

‘Hatchet-shaped, p. 131. f. 99. Three-edged, Me-

sembryanthemum deltoides > f. 100. Four-edged :

392 EXPLANATION

Tab. 8. f.:101. Alienated, Mimosa verticillata,
p. 132. f. 102. Hooded, Sarracenia, p. 133.

_ f. 103. Furnished with an appendage, Dionea
muscipula: f. 104. Jointed, Fagara tragodes, -
p. 135. f. 105. Binate, p. 135. f. 106. Ternate :
jf: 107. Interruptedly Pinnate, p. 136. (f. 108.
Pinnate in a lyrate form, p. 136. ,f. 109. Pinnate
in a whorled manner, p. 137. ,f. 110. Auricled :
f- 111. Compound, p. 138. 112. Doubly com-
pound, or Twice ternate: (f. 113. Thrice com-
pound, or Thrice ternate: f. 114. Pedate, Hel-
leborus, p. 139.

TaB. 9, Appendages. /. 115. Stipulas of Lathyrus
latifolius, p. \66; also an abruptly pinnated leaf,
ending in a tendril, p. 135. f. 116. Stipulas united
to the footstalk, in Rosa, p. 166; also a pinnated
leaf with a terminal leaflet, p. 135. f. 117. Floral
leaf of Tilia, p. 168. _f. 118. Coloured floral
leaves, Lavandula Stoechas: f. 119. Spinous
ones, Atractylis cancellata: f. 120. Thorns,
LTippophie rhamnoides, p. 169. _f. 121. Prickles,
p.170. f. 122. Tendril, Lathyrus latifolius :
fe 123. Glands of the Moss Rose, p. 172. f. 124.
Hairs: f. 125. Bristles of Echium pyrenaicum,
p. 17S. . chad

Tas. 10. Inflorescence. nh 196. Whorl, in Lamium,
p» 175. ff. 127. Whorled leaves, and axillary

OF THE PLATES. 393

flowers, of Hippuris vulgaris, p.175. _f. 198.
Cluster, Rides: f. 129. Spike, Ophrys spiralis :
J. 130. Less correct Spike, Veronica spicata,
p- 176. f. 131. Spikelet, Bromus, p. 177. f. 139.
Coryinb: f. 133. Corymbose fascicle, Achillea,
p. 178. f. 134. Fascicle, Dianthus Armeria,
p. 178. f. 135. Head or Tuft, Trifolium: f. 136.
Simple Umbel, Eucalyptus piperita, p. 179. f. 137.
Simple Umbel in the natural order of Umbellate,
Astrantia major, with the involucrum, a: |

Tas. 11. f. 138. Compound Umbel, Laserpitium
simplex, with its general Involucrum, a, and partial
one, 6, p. 187. f. 139. Cyme, Laurustinus,
p. 180. jf. 140. Panicle, Oat, p. 180. f. 141.
Bunch, Common Vine, p. 181.

Calyx. f. 149. Perianthium, or Calyx properly
so called, Dianthus deltoides, p. 186. f. 143.
Involucrum, so called, in Anemone, p. 181. f. 144.
Involucrum or Jndusium of Ferns, p. 189. f. 145.
One of the same separate, with a capsule and its
ring. f. 146. Catkin of the Hazel-nut, p. 190.

Tab. 12. Calyx and Corolla, with Nectary. f. 147.
Sheath of the Narcissus; a, the Petals, called by
Jussieu, Calyx ; 5, the Crown or Nectary, see p. 200.
Jf. 148. Husk of Grasses, p. 191. f: 149. Awns.
JF 150. Sealy Sheath, Pterogonium Smithii, p. 192.
J. 151. Veil of the same, p. 192, 202. f. 152.

394 : EXPLANATION

Jungermannia epiphylla, showimg a, the Calyx,
p- 1925, the Veil or Corolla, p. 192, 202 ; and
c; the unopened Capsule. f..153.. Wrapper,
| Agaricus : f. 154. Radical Wrapper, p:. 193.
f-155: MonopetalousSalver-shaped Corolla, p.195.
f. 156. Polypetalous Cruciform Corolla: .f. 157.
A-separate Petal of the same; a, Claw; 5, Border;
fe 158. Unequal Corolla, Butomus, p.. i195.
Tas. 13. f..159. Bell-shaped Corolla; f. 160.
Funnel-shaped: f. 161. Ringent: f: 162. Per-
sonate, Antirrhinum reticulatum, p. 196. f. 163.
Papilionaceous, Lathyrus: f. 164. Standard of
the same; f. 165. One of the wings; f. 166.
Keel; f- 167. Stamens, Style, &e.; jf. 168. In-
complete Corolla, Rittera. f. 169. Peéloria, or
regular flowered variety of Antirrhinum. Linaria,
pel97 f-170. Nectary in the Calyx of -Tro--
peolum: f..171. Nectary of Aquilegia; p. 203.
Ff. 172, 173. Thesame part in Kpimedium'> fo 174.
Pair of Nectaries in Aconitum, p. 903. f..175.
Fringed Nectaries in anaes p- 204. |

Tan.'14. Stamens, Pistils and Fruit. f. 176... A
Stamen: a, filament; 5, anther, p. 206, 207.
Si 177~ Pistil: a, germen; d, style; .c, stigma,
p» 208, 209. 2178. Capsule’ of amannual Je-
sembryanthemum, open and shut, p. 201. f-179. —
Transverse'section of the capsule of Datura, p.212,

OF THE PLATES. . 395

showing the partitions and columelie. 7. 180.
Siliqua, or Pod: f. 181. Stlcula, or Pouch,
pools. f. 182. Legume; p: 214. of. 183. Stone-
fruity p. 2lSv> f.d84. Apple: (f. 185. Berry:
Jf. 186. Compound» Berry; p. 216. f2.187. Berry
of Passiflora suberosa, p. 216: f- 1882 Cone,
Larch, p. 218. f. 189. Capsule of a Moss,
Splachnum, with its fleshy base, or apophysis, a,
and fringe, 6, p. 371, 373.

TaB. 15. f. 190. Barren flower of a Moss, much
magnified, after Hedwig: (f: 191. Stamens; with
the Pollen coming forth, and the jointed filaments,
p- 371. f. 199. Fertile flower of a. Moss, con-
sisting-of numerous pistils, only one of which in
general comes to perfection. They are also.accom-
panied by jointed filaments: (f. 103. A. germi-
nating seed of Gymnostomum pyriforme, from
Hedwig likewise, showing its expanding embryo :

fi 194. The samesmore advanced: f. 195. The
same much further advanced, and become.a young
plant, showing its Jeaves and branched cotyledons,
pi22i. ff. 196. Young plant of Lunaria hygro-
metrica, exhibiting the same parts, p.372. fo 197.
Powdery wart of a Lichen, presumed to be its
barren flower: —f. 198. Perpendicular section,
magnified, of the Shield or fruit of a Lichen,
showing the seeds imbedded in its disk, p. 376.
f. 199. Section of the seed of a Date, Phenw

Pa]

396 EXPLANATION OF TILE PLATES.

dactylifera, from Gzertner, the bulk of which is a
hard Albumen, p. 222, having a lateral cell in
which is lodged the horizontal embryo, a, p. 220.
f. 200. Section of the Vitellus in Zamia, from the
same author, with its embryo a, with which it is,
like a cotyledon, closely connected, p. 223. f. 201.
Rough coats of the seeds in Cynoglossum, p. 227.
f. 202. Arillus of a Carev, p. 998, Je203.
Seed of 4/zelia, with its cup-shaped Arillus, p. 226.
f. 204. Pappus, or Seed-down, of Tragopogon,
p. 229. (f. 205. Tail of the seed in Dryas:
f. 206. Beaked fruit of Scandiv, with its seeds
separating from their base, p. 230. fi. 207. Winged
seed of Embothrium, p. 230. f. 208. Section of
the conical Receptacle of the Daisy, with its calyx :
f. 209. Cellular Receptacle of Onopordum, p. 233.
f. 210. Ligulate floret with both stamens and pistil,
in a Dandelion, p. 235. _f. 211. Ligulate floret
with only a pistil, in the radius of a Daisy, p. 234.
f. 212. Tubular floret from the disk of the same,
_ having stamens and a fertile pistil, p. 235. f. 213.
Capsule of a Moss with a double fringe, the lid
shown apart, p. 371. _f. 214. A portion of the
same fringe magnified, p. 373.

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397

I. INDEX of remarkable Plants, or those of which any
particular Mention, or any Cliange in their Classifi-

cation, is made.

Asroma, 341

Abrus preeatorius, 339
Acer, 321

saceharinum, 52
LEsculus Hippocastanum,105
Agrimonia, 278, 325
Ailanthus, 284, 366

Algw, 375—378
Alopecurus bulbosus, 88
Amaranthus, 284
Amaryllis formosissima, 244
Ambrosinia, 356, 362
Anagallis, 251
Angiopteris, 295

Annona hexapetala, 171
Aponogeton, 319, 324
Aquilicta, 361

Arenaria, 276, 285
Aristolochia Clematitis, 256
Sipho, 257, 294
Arum, 62, 70, 202, 356, 362
Ash, 47, 88, 98
Asperifolia, 515
Athrodactylis, 284, 364
Atriplex, 367

_ Aucuba, 284

Bamboo, 58, 283
Barberry, 248
Bauhinia, 287
Black rose, 67
Blandfordia, 276
Bonapartea, 280
Brodiea, 201

Browallia, 291
Bryonta, 301
Bulbroma, 341
Buffonia, 291

Cactus coccinellifer, 259

Cenopteris, 295

Calamagrostis, 294

Calceolaria, 285

Calla, 356, 362

Canna, 351

Cannabis, 251, 365

Capura, 318

Carpinus Betulus, 190

Caryocar, 528

Caryophyllus, 525

Celosia, 247

Ceratonia, 368

Ceratopetalum, 285

Chara, 359

Cherry, double-blossomed,
210

Chrysanthemum indicum, 62

Cistus creticus, 144

Citrus, 342

Cleome, 327, 332

Climbing plants, 92

Cluytia, 305

Coffee, 262

Columnifere, 334

Conchium, 285

Conferva bullosa, 162

Contorte, 316, 353

Coriaria, 366

398

Cornus mascula, 52, 143

Corymbium, 347

Cucumis, 301

Cucurbita, 301

Cuscuta, 73, 79

Cyamus Nelumbo, 221, 224,
283, 295 ie

Cycas revoluta, 252

Cytinus, 355

Darea, 295

Devil’s-bit, 88
Dicksonia, 287
Dictamnus albus, 144
Dillenia, 287

Dionea muscipula, 153, 151
Dodecutheon Meadia, 69
Dog-rose, 264
Dombeya, 75, 220
Dorstenia, 287
Dracontium, 356
Duranta, 290

Epimedium alpinum, 275
Eriocalia, 284
Ervum, 337
Euclea, 366

.

Euphorbia, 249, 285, 368

Ferns, 369

Ficus, 256, 368
Filices, 369

Flores tristes, 59 °
Fontatnesia, 286 |
Fraxinus Ornus, 144 |
Fungi, 379—38]

Gentiana, 285

— Glaucium phenicium, 246
Glycyrrhiza, 284
Goodenia, 285

Gourd tribe, 361, 365
Grasses, 313, 560, 367

INDEX If.

Grewia, 350
Guettarda, 301
Gundelia, 285
Gypsophila, 285

Hasiingia coccinea, 306

“Hedysarum gyrans, 160

Helianthus annuus, 52, 142,

1569, 284 od
tuberosus, 83,, 84

Helicteres, 350

Hemerocallis, 276, 284

Hemp, 51.) 4

Hepatice, 374

Hernandia, 287

Hillia, 291

Hippomane Manceinella, 155

Hippophae rhamnoides, 226,
365

Hippuris, 241

Holmskioldia, 307

Hop, 144

Horseschesnut, 105 —

Humea, 286

Jairopha urens, 244

Jerusalem artichoke, 83.

Jungermannia, 192, 202,
375, 370

Kalmia, 247
Kleinhovia, 356
Knappia, 287

Lace-bark, 21
Lachenalia tricolor, 86
Lasiopetalum, .285 9)
Lathyrus Aphaca,. 168
Lavatera arborea, 80
Leea, 301 |
Lemna, 241, 559
Lichen, 376—377
Liliaceae, 518

INDEX I.

Lilium bulliferum, 86,208
Linnea; 237, :291-
Lithospermum, 234
Liverworts, 374) |

Lobelia longiflora, 155
Lonicera cerulea, 104
Luride, 3\5

Magnolia, 287
Maltese oranges, 68
Malvacee, 334
Marchantia, 375
Meadow Safiron, 241
Melaleuca, 542
Mentha, 173
Mimosa pudica, 32, 160
—— sensiliva, G0
Miralilis, 354
Monocotyledones, 45
Monsonia, 341
Morus, 360
Mosses, 192, 202, 221;241,
370—374
Murrea, 29i
Musa, 242
Musci, 370—S74
Mussenda, 169
Miyosotis, 175
Myristica, 307
Myrti, 325

Nandina domestica, 585

Nastus, 288

Nelumlblium, 283

Nepenthes distillatorta, 133,
150, 352, 367

Nopal, 239

Norfolk island, pine of, 75,
220

Nymphea, 148, 156, 253,
ce ee |

Omphalea, 363

399

Orchide@, 84,
BSS
Origanum, 234 |
Ornithopus perpusillus, 109
Orobus sylvaticus, 136. —
Oxalis sensitiva, 160

348--+351,

Palme, 45, 48,108, 238,
245, $81—382

Pandanus, 284, 304

Papilionaceee, 322,335—340

Passiflora, 333 |

Periploca greca, 353

Phleum pratense, .32,°87

Phyllachne, 351

Pine-apple, 241

Pinus, 362

Pistacia Lentiseus, 264

Pistia, 333, 355

Plane-tree, its buds, 104

Pomacee, 325

Populus dilatata, 144

Potamegeton, 148

Pothos, 356°

Precia, 315 —

Primula marginata, 69

Pieris, 295

Rhapis, 245
Rhodiola, 301
Rivularia, 378
Rosace@, 318, 325 .
Rotacee, 315
Rubiaceae, 167
Rumex sanguineus, 57
Rutacee@, 227, 522
Ruta graveolens, 247.

Salix, 358

Salvia pomifera, 264 —
Sarracenia, 148, 277
Scheuchzerta, 287
Scitaminee@, 311, 351, 353

AOO

Scopolia, 355
Sertphium, 347
Silene inflata, 200
Sisyrinchium, 332
Smithia sensitiva, 160, 288,
338
Solandra _esagssitl 108
Spergula, ¢ rec
es ge 28
culia, 325, 3638
Stilago, 352
Strelitzia, 286
Strumpfia, 352
Stwartia, 286
Stylidium, 351—

Tabasheer, 58
Tamarindus, 333
Taxus nucifera, 2t8
Thea, 335, 342
Theobroma, 340
Tmesipteris, 205

INDEX I.

Tournefortia, 286
,Tragopogon major, 265
‘Tropeolum, 320
Tulbaghia, 201

Umbellifere, 316
Uredo frumenti, 265

Valisneria spiralis, 255, 364
Vaucheria, 378

Ventenatia, 352

Viscum album, 158

Willows,
398

27, 47, 143, 264,
Xanthe, 367

Xylopia, 356

Yew, 217

Zostera, 357 see

401

II. Index to the Explanations and Illustrations of
technical ‘Terms.

Asnrvrt leaves, 122, 135
Acaules, planta, 98
Acerosum, folium, 118
Acinaciforme, fol. 131
Acinus, 217, 225
Aculeus, 170
Acuminatum, folium, 123
Acutum, fol. 123 -
Adpressa, folia, 113
Adscendens, caulis, 91
Aggregate flowers, 235
Aggregati, pedunculi, 101
a, 196, 230
Alatus, caulis, 96
Allumen, 22\—224
Alburnum, 26
Alienatum, hea 132
Alterna, folia, 111, 136
Alterné ramosus, caulis, 94
Amentum, 189, 190, 235
Amplexicaulia, folia, 115
Anceps, caulis, 95
» folium, 131
Angiocarpi, fungi, 380
Anthera, 206
Aphylle, planta, 111
Apophysis, 371
Apothecium, 377
Appendages, 166
of the seed, 225
Appendiculatum, fol. 133,
150

\

Apple, 215
Arillus, 226—228
Arista, 191

Arrow-shaped leaf, 120

Articulata, radix, 87

Articulatum, folium, 134,
136

Articulatus, caulis, 95

, culmus, 99

Artificial systems, 27 1—273,
296

Auriculatum, folium, 137

Avenium, fob. 128

Awl-shaped leaf, 130

Awn, 191

Axillaris, pedunculus, 100

Bacca, 215—218
Bacillum, 377
Barren flowers, 234
asi trinerve, folium, 128
Beak, 230 ane
Beard, 191
Berry, 215—218
Biflori, peduneuli, 101
Bigeminatum, folium, 138
Bilobum, fol. 121
Bina, folia, 112
Binatum, folium, 135
Bipinnatifidum, fol. 122
Bipinnatum, fol. 138
Biternatum, fol. 138
Blistery leaf, 127
Blunt leaf, 123
Botany, 8
Brachiatus, caulis, 94
Bractea, 168, 169, 188
Bullosa, radix, 86

2D

402

Bullatum, folium, 127
Bunch, 181

Calyptra, 192, 202, 370

Calyx, 186—1i94

Cambium, 29

Campanulata, corolla, 196

Canaliculatum, folium, 130

Capitulum, 178

Capsula, 212, 213

Carina, 197

Carinatum, felium, 131

Carnosum, fol. 130

Cartilagineum, fol. 124

Catkin, 189, 190, 218, 2

Catulus, 189

Cauda, 230

Caudex, 79, 80

Caulina, folia, 111

Caulinus, pedunculus, 100

Caulis, 90

Cellular integument, 18

Central vessels, 39

Channelled leaf, 130

Characters of plants, 278—
282, 330

Ciliatum, folium, 124

Cimeter-shaped leaf, 131

Circumscissa, capsula, 314

Cirrosum, folium, 124, 135

Cirrus, 170—172

Climbing stems, 92

Cloven leaf, 121

Cluster, 175

Coarctata, panicula, 181

Coccum, 213°

Coloratum, folium, 129

Coloured leaf, 129

Columella, 212

Coma, 229 __.

Completus, flos, 233

Composita, folia, 116, 134—
1359

INDEX II.

Compound flowers, 234,

348—348, > |

— leaves, 116, 134
—159

Compressum, folium, 13
Concavum, fol. 128
Conduplicatum, fol. sie
Cone, 218
Conferta, folia, 111
Conjugatum, folium, 137
Connata, folia, 115
Corculum, 74, 219
Cordatum, folium, 120
Coriaceum, fol, 132 ©
Corolla, 194—206, 269
Corymbus, 177
Costatum, folium, 128
Cotyledons, 74, 220—224
Crenatum, folium, 125 —
Crescent-shaped leaf, 120
Crispum, folium, 127
Cruciformis, corolla,
331, 332
Cucullatum, folium,
148
Culmus, 98
Cuneiforme, folium, 118
Cup of the Flower, 186—194
Curled leaf, 127. —
Cuspidatum, folium, 123
Cuticle, 13
Cylindrical leaf, 130
Cyma, 180, 188, 236, 237
Cyphella, 377

196,

133,

Deciduum, folium, 132
Decompositum, fol. 138
Decurrentia, folia, 116, 138
Decussata, fol. 112
Deltoides, folium, 119
Demersa, folia, 114

Dentatum, folium, 124 .
Depressa, folia, 114 —

INDEX II.

Depressum, folium, 130

Determinaté ramosus, caulis,

Q4
Diamond-shaped leaf, 119
Dicotyledones, 75
Diffusa, panicula, 181
Diffusus, caulis, 93
Digitatum, folium, 135
Dioici, flores, 234, 501
Discus, 235
Dissectum, folium, 121
_ Dissepimentum, 212
Disticha, folia, 112
Distichus, caulis, 94
Dolabriforme, folium, i5
Down of the seed, 228 ©
Drupa, 215, 217 i
Dust of the anther, 207

Ellipticum, folium, 118
Emarginatum, fol. 123
Embryo, 74, 2}
Limersa, folia, 114
Enerve, folium, 128
Enodis, culmus, 99
Ensiforme, folium, 151
Entire leaf, 124
Epidermis, 13
Bquitantia, fotia, 115
Erecta, folia, 115
Erecius, caulis, 91
Erosum, folium, 125
Evergreen leaves, 132
Excitability, 50

Fall of the leaf, 260
Fasciculata, folia, 112 °
Fasciculatus, caulis, 98
Fasciculus, 178
Fertile flowers, 234
Fibrosa, radix, 81
Fiddle-shaped-leaf, 120
Filamentum, 206

40

Fingered leaf, 135
Fissum, folium, 121
Flagelliformis, caulis, 93
Fleshy leaf, 130
Flexuosus, caulis, 93
Floral leaf, 168

Flores tristes, 59

Florets, 234

Florifera, folia, 116
Flosculi, 254

Folium, 110

Folliculus, 213

Forcing, 69

Fringe of mosses, 373
Fringed leaf, 124

Frons, 102

Fulcrum, 160
Funnel-shapped corolla, 196
Fusiformis, radix, 82

Galbulus, 217
Galls, 263—265 °
Gemma, 104
Gemmaceus, pedunculus, 101
Geniculatus, cuimus, 99
Genus, genera, 274—280
Germ, 219 |

_ Germen, 208—210

Gibbum, folium, 130
Glaler, 96

Gland, 172
Glandula, 172
Glandulosum, folium, 126
Glaucus, 97

Gluma, 191, 236
Grafting, 66
Granulata, radix, 87
Gymnccarpi, fungi, 380

Hairs of plants, 172-174
Halberd-shaped leaf, 120
Hastatum, folium, 120
Hatchet-shaped leaf, 131

2D 2

404

Heart-shaped leaf, 120
Herbarium, 382988" dei
Hilum, 225

Hirtus, 97

Fispidus, 97

Hollow leaf, 128, 130
Honey, 198, 203—206
Honey dew, 144

Hooded leaf, 133, 148 —
Horizontalia, folia, 113°
Husk, 191 ~

Hymenium, 380
Hypocrateriformis, corol. 196

Imbricata, folia, 112
Immersa, folia, 114
Incanus, 97

Incisum, folium, 121
Incompleta, corolla, 197
Incompletus, flos, 233
Incurva, folia, 115°
Indusium, 189

Inequale, folium, 122
Inerme, folium, 124
Inflexa, folia, 113°
Inflorescentia, 175
Infundibuliformis, corol. 196
Integerrimum, folium, 124
Integrum, fol. 117,124
Internodis, pedunculus, 101
Involucellum, 188
Involucrum, 187-189, 236
Involutum, folium, 126
Iulus, 189

Jagged leaves, 125
Jagged-pointed leaves, 123
Jointed leaf, 134, 136

Keel, 197

Keeled leaf, 131

Kidney- shaped leaf, 119
Laciniatum, folium, 121

INDEX Ii.

Leavis, 96

Lamelle, 380

Lamina, corolla, 195
Lanatus, 97

Lanceolatum, folium, 118
Lateralis, pedunculus, 101
Laxus, caulis, 93 |
Leathery leaf, 132
Legumen, 214

Tike, 99

Ligulati, flosculi, 254
Limbus, corolle, 195
Lineare, folium, 118
Lingulatum, folium, 132
Lion-toothed leaf, 120
Lirella, 377

Lobatum, foltum, 117, 121
Lobed leaf, 117, 121
Lunulatum, folium, 120
Lyratum, fol. 120, 136

Maculatus, 97

Medulla, 30

Membrana, 224

Membranaceum, folium, ¥ 132

Monocohylenene ian 45,
79, 171, 221

Monoici, flores, 234, 300

Mucronatum, folium, 125

Multiflori, pedunculi, 102

. Mutica, gluma,191_

Naked flowers, 238

leaf, 129

Natantia, folia, 114

Natural systems, 271—274,
S09 .

Nectarium, 194, 205—206

Needle-shaped leaf, 118°

Nervosum, folium, 128

Nicked leaf, 123

Nitidus, 96

Nomenclature, 282 — 295

INDEX II.

Notched leaf, 125
Nucamentum, 189 .
Nudum, folium, 129
Nudus, flos, 235
Nut, 215

Obliqua, folia, 115

Oblique leaf, at the base, 122
Oblongum, folium, 118
Obovatum, folium, 117 .
Olbtusum, folium, 125...
cum acumine,

125
Ocrea, 169. | |
Opposita, folia, 111, 156
Oppositifolius, pedunculus,
101

Orbiculatum, folium, 117
Ovale, folium, 118
Ovatum, folium, 117...

Palmatum, folium, 122

_ Panduriforme, folium, 120
Panicula, 180 :
Papilionacea, corolla, 196
Papillosus, 96.

Puappus, 228

Partitum, folium, 121
Patentia, folia, 113
Pectinatum, folium, 122
Pedatum, folium, 139
Pedicellus, 100
Pedunculus, 100
Pellicula, 226

Peltata, folia, 115
Pentagenus, caulis, 95
_Pepo, 216

Perfect flowers, 233.
Perfoliata, folia, 115
Perianthium, 186 |
Pericarpium, 186, 211—219
Perichetium, 192
Peridium, 381

405

Peristomium, 373
Personata, corolla, 196
Petalum, 185, 194 .
Petiolata, folia, 114
Petiolus, 102

Pileus, 381

Pilosus, 97

Pilus, 172—174
Pinnatifidum, folium, 122
Pinnatum, fol. 135—-137
Pistillum, 185, 208—211
Plaited leaf, 127 .
Plicatum, folium, 127
Plumula, 75

Pod, 213

Podetium, 377

Pointed leaf, 123
Pollen, 207

Pomum, 215

Pouch, 214

Premorsa, radix, 83
Premorsum, folium, 123
Prickles 170). weisich:-ahs
Procumlens, caulis, 91 |
Prolifer, caul. 94.
Prostratus, caul. 94. .
Pubes, seminis, 229...
Pubescence, 172—174
Punctatum, folium, 126

uadrangulare, folium, 119
I A caulis, 95
Quaterna, folia, 112. .
uina, folia, 112
ae folium, 135
Quinquangulare, fol. 119
Quinquangularis, caulis, 95

Racemus, 175
Radicalia, folia, 111
Radicans, caulis, 91
Radicula,79
Radius, 235. .

406

Ramea, folia, 111
Rameus, pedunculus, 100
Ramosissimus, caulis, 94
Rays, 235 sy
Receptaculum, 186; 252--235
Reclinata, folia, 113
Rechinatus, caulis, 9\
Rectus, cuulis, OS
Recurva, folia, 113
Reflexa, folia, 1V5
Reniforme, folium, 119
Repandum, folium, 126
Repens, caulis, OV

—, radix, 82
Resupinata, folia, 113
Retusum, folium, 123
Revolutum, folium, 126
Rhombeum, folium, 119
Ribbed leaf, 128
Ribless leaf, 128
Ringens, corolla, 196
Rosacea, corolla, 196
Rostrum, seminis, 25
Rotata, corolla, 196
Rugged leaf, 127
Rugosum, folium, 127
Runcinatum, folium, 120

Sagittatum, folium, 120
Salver-shaped corolla, 196
Samara, 212

Sarmentosus, caulis, 93
Scaber, 95

Scaly roots, 86
Scandens, caulis, G2
Scapus, 09

Sear of the seed, 205
Secunda, folia, 113

Seed, 186, 219—239
Seed-vessel, 186, 211-219
Semen, 186, 219—232
Semicylindraceum, fol. 130
Sempervirens, folium, 132

INDEX 11.

Separated flowers, 233
Serratum folium, 125
Serrulatum, folium, 125
Sessiles, flores, 102 |
Sessilia, folia, 115

Sharp leaf, 123
Sheath, 190, 192, 236
Sheathing leaves, 115
Shrubs, 104

Silicuia, 214

Siliqua, 215

Silver grain, 41

Simplicia, folia, 116
Stnuatum, folium, 121
Solitarius, pedunculus, 101
Spadix, 190, 202 )
Sparsa, folia, 111

Sparsi, pedunculi, 101
Spatha, 190 —
Spatulatum, folium, 118 ©
Species of plants, 274—282
Spica, 176—178
Soicula, 177
Spike, 176—178
Spikelet, 177
Spina, 169
Spinosum, folium, 124 ©
Spiral vessels, 37
Spore, 377

Sporangium, 377 —
Stamen, 185, 206—208
Standard, 196

Stigma, 209

Stipes, 103

Stipula, 166—168

Stone fruit, 215 ‘
Striatus, 97

Sirictus, caulis, 93
Strobilus, 218
Strophiolum, 251.

Stylus, 208

Submersa, folia, 114
Subrotundum, folium, 117

INDEX Il. AO7

Subsessile, folium, 134
Subulatum, folium, 130
Sulcatus, 97

Supradecompositum, fol. 138

Sword-shaped leaf, 131

Tail of a seed, 230
Tendril, 170—172
Teres, caulis, 95

» folium, 130
Terminalis, pedunculus, 101
Terna, folia, 112
Ternatum, folium, t35
Testa, 224

Tetragonum, folium, 132
Tetragonus, caulis, 95
Thallus, 377

Thorn, 169

Thyrsus, 181
Tomentosus, 97
Tongue-shaped leaf, 152
Toothed leaf, 124
Triangulare, folium, 119
Triangularis, caulis, 95
Trice, 377

Trigonum, foltum, 131
Trigonus, caulis, 95
Trilobum, folium, 121
Trinerve, folium, 128
Triplinerve, folium, 129
Trigueter, caulis, 95
Triquetrum, folium, 131
Trowel-shaped leaf, 119
Truncatum, folium, 122
Tuberosa, radix, 83
Tubular leaf, 130 _
Tubulosi, flosculi, 235
Tubulosum, folium, 130
Tubus, 195

Tuft, 178

-Tunic, 226—228

“Umbella, 179, 187, 235, 237

Undivided leaf, 117
Undulaium, folium, 127
Unequal leaf, 122
Unguis, 195
Uniflori, pedunouli, 101
United flowers, 255
Utriculus, 212

Vaginantia, folia, 115
Variegatum, folium, 129
Varieties, 1O6—~109, 274.
Veil, 20%, 3.61 |
Veinless leaf, 128

Veiny leaf, 128
Venosum, folium, 128
Verrucosus, 96
Verticalia, folia, 115
Verticillata, folia, 112
Verticillus, 175
Vexillum, 196

Villosus, 97

Viscidus, 96

Vitellus, 222—224
Volubilis, caulis, 92
Volva, 193

Wavy, 126
Whorl, 175
Whorled, 112, 137
Wing, 230 |
Wrapper, 193

Y oked leaf, 137
Yolk, 222924

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which sometimes appear of the same plant in our monthly writers.
This he is the more desirous of attending to, as his work is not limited
to plants already in cultivation in England, being occasionally en-
riched with drawings and specimens of totally new productions, from
India more particularly, which may, when known, be procured from
abroad.

6. A Sxercu of a Tour on the ContineExT, in 3 Vols. 8vo. 2d edition,
1807. Price 1]. 4s.——With several other botanical works.

7. Lacuesis Larponrca, or a Tour in Lapland, translated from the
original unpublished manuscript Itinerary of the celebrated Lin-
wus, by Sir J. E. Sarr, with above 60 wooden cuts from extempo-
raneous sketches of the illustrious author. In 2 vols. 8vo. 1811.
Price 11. 1s.

8. ConsIDERATIONS respecting CAMBRIDGE, more particularly relating
to its Botanical Professorship. Price 2s. 6d.

Printed by Richard and Arthur Taylor, Shoe-Lene.

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